Nuclear Proliferation Case Studies

Appendix to Safeguards to Prevent Nuclear Proliferation information paper

(Updated September 2016)

  • North Korea made weapons-grade plutonium using a research reactor and a reprocessing plant in defiance of its NPT obligations. In 2006, 2009 and February 2013 it exploded nuclear devices.
  • In 2002 Iran's previously undeclared nuclear facilities became the subject of IAEA inquiry, which established that it appeared to be in violation of its NPT safeguards agreement. It continued uranium enrichment in defiance of the UN Security Council.
  • Iraq to 1991 attempted to enrich indigenous uranium to weapons-grade material, in violation of NPT and Safeguards obligations.
  • Syria constructed a nuclear reactor in breach of its NPT obligations.


Up to the late 1980s it was generally assumed that any undeclared nuclear activities would have to be based on the diversion of nuclear material from safeguards. States acknowledged the possibility of nuclear activities entirely separate from those covered by safeguards, but it was assumed they would be detected by national intelligence activities. There was no particular effort requiring the IAEA to attempt to detect them.

Not until the 1990 NPT Review Conference did some states raise the possibility of making more use of the provisions for "special inspections" in existing NPT Safeguards Agreements, for example. Special inspections can be undertaken at locations other than those where safeguards routinely apply, if there is reason to believe there may be undeclared material or activities.

However, inspections in Iraq following the 1991 UN Gulf War cease-fire resolution showed the extent of Iraq's clandestine nuclear weapons program, and it became clear that the IAEA would have to broaden the scope of its activities. Iraq was an NPT Party, and had thus agreed to place all its nuclear material under IAEA safeguards. But the inspections revealed that it had been pursuing an extensive clandestine uranium enrichment programme, as well as a nuclear weapons design programme.

The revelations from Iraq provided the impetus for a very far-reaching reconsideration of what safeguards are intended to achieve. (See the section on Addressing Undeclared Nuclear Activities in the main paper on Safeguards to Prevent Nuclear Proliferation.)

North Korea

The Democratic People’s Republic of Korea (DPRK) provides an example of safeguards succeeding in their aim of detecting violations of non-proliferation obligations – in this case one of long standing. It was subsequently brought to the attention of the international community, with diplomatic pressure being applied through the UN Security Council.

The DPRK acceded to the NPT in 1985 as a condition for the supply of a nuclear power station by the then USSR. However, it delayed concluding its NPT Safeguards Agreement with the IAEA, a process which should take only 18 months, until April 1992. This delay was apparently related to the presence of US tactical nuclear weapons in South Korea, which were withdrawn in 1992. IAEA inspections then showed up some problems.

Plutonium programme

During that period, in late 1985, North Korea brought into operation a small gas-cooled (CO2), graphite-moderated, natural-uranium (metal) fuelled "Experimental Power Reactor" of about 25 MWt at Yongbyon, on the west coast 55 km north of Pyongyang. It exhibited all the features of a plutonium production reactor for weapons purposes and produced only about 5 MWe. North Korea also made substantial progress in the construction of two larger reactors designed on the same principles, a prototype of about 200 MWt (50 MWe) at Yongbyon, construction started 1985, and a full-scale version of about 800 MWt (200 MWe) at Taechon, 25 km north of Yongbyon.

In addition it completed and commissioned a reprocessing plant at Yongbyon for the extraction of plutonium from spent reactor fuel. That plutonium, if the fuel was only irradiated to a very low burn-up, would have been in a form very suitable for weapons. The existence of the plant was revealed by IAEA inspectors. Although all these facilities at Yongbyon were to be under safeguards, there was always the risk that at some stage, the DPRK would withdraw from the NPT on some pretext and use the plutonium for weapons.

One of the first steps in applying NPT safeguards is for the IAEA to verify the initial stocks of uranium and plutonium to ensure that all the nuclear material in the country have been declared for safeguards purposes. While undertaking this work in 1992, IAEA inspectors found discrepancies which indicated that the reprocessing plant had been used more often than the DPRK had declared. This suggested that the DPRK could have weapons-grade plutonium which it had not declared to the IAEA. Information passed to the IAEA by a member state (as required under the IAEA's Statute) supported that suggestion by indicating that the DPRK had two undeclared waste or other storage sites.

In February 1993 the IAEA called on the DPRK to allow special inspections of the two sites so that the initial stocks of nuclear material could be verified. The DPRK refused, and on 12 March announced its intention to withdraw from the NPT (three months notice is required). In April 1993 the IAEA Board concluded that the DPRK was in non-compliance with its safeguards obligations and reported the matter to the UN Security Council. In June 1993 the DPRK announced that it had "suspended" its withdrawal from the NPT, but subsequently claimed a "special status" with respect to its safeguards obligations. This was rejected by IAEA.

Once the DPRK's non-compliance had been reported to the UN Security Council, the essential part of the IAEA's mission had been completed. Inspections in the DPRK continued, although inspectors were increasingly hampered in what they were permitted to do by the DPRK's claim of a "special status". However, some 8,000 corroding fuel rods associated with the experimental reactor remained under close surveillance and any plans to separate plutonium from them were deferred, in the event, for eight years.

Following bilateral negotiations between DPRK and the USA, and the conclusion of the agreed framework in October 1994, the IAEA was given additional responsibilities. The agreement required a freeze on the operation and construction of the DPRK's plutonium production reactors and their related facilities, and the IAEA was responsible for monitoring the freeze until the facilities were eventually dismantled. The DPRK remained uncooperative with the IAEA verification work and did not comply with its safeguards agreement, though apparently no further work was done on the two larger reactors at Yongbyon and Taechon.

Iraq was defeated in a war, which gave the UN the opportunity to seek out and destroy its nuclear weapons program as part of the cease-fire conditions. The DPRK was not defeated, nor was it vulnerable to other measures, such as trade sanctions. It could scarcely afford to import anything, and sanctions on vital commodities, such as oil, would either have been ineffective, or risk provoking war.

Ultimately, the DPRK was persuaded to halt its nuclear weapons program in the 1990s in exchange, under the agreed framework, for about $US5 billion in energy-related assistance. This included two 1000 MWe light water nuclear power reactors. There was also the prospect of diplomatic and economic relations with the USA.

Light-water reactors offered

At the end of 1999 The long-awaited contract to build two 1000 MWe light-water reactors was signed, enabling construction to begin. The agreement was between the Korean peninsula Economic Development Organisation (KEDO) – the international organisation in charge of the project – and the South Korean utility KEPCO, bringing technology to build a nuclear power plant which is not amenable to misuse. KEDO was set up following the 1994 deal involving the USA to head off the production of weapons plutonium from the small gas-graphite reactor and to provide much needed energy – in the short term fuel oil, but eventually electricity.

The Korean Standard Nuclear Plant (KSNP) reactors were the same as those then being built in South Korea, and were expected to be completed in 2008. South Korea committed to provide US$ 3.22 billion for the US$ 4.6 billion project, with Japan contributing US$ 1 billion and the EU most of the balance.

In August 2002, with the project running several years behind schedule due to North Korea's continued lack of cooperation with the IAEA in verifying the history of its nuclear program, first concrete for the two-unit nuclear power plant was poured at Kumho, on the east coast. This formal start of construction was a milestone for KEDO, which planned to deliver the main components in 2005. The work would then stop unless North Korea was fully compliant with IAEA requirements regarding verification of past activities (specifically, that all nuclear material held by North Korea has been declared and placed under safeguards).

Plutonium program revived

In December 2002 DPRK removed the IAEA seals on its facilities at Yongbyon and ordered the IAEA inspectors out of the country. It then restarted its small reactor and commenced reprocessing the 8000 irradiated fuel rods to recover weapons-grade plutonium. In April 2003 it withdrew from the NPT – the first and only country to do so.

Since 2003 negotiations have been intermittently under way to secure some agreement on curtailing North Korea's nuclear weapons program. These have involved China, South Korea, Japan, Russia and the USA, which insisted upon "complete, verifiable, and irreversible dismantling of North Korea's weapons programs" through "diplomatic dialogue in a multilateral framework involving those states with the most direct stakes in the outcome."

Construction of the new nuclear power reactors under KEDO was suspended late in 2003 with the first unit about 30% complete, and this suspension was renewed in 2004 and 2005. The KEDO board formally terminated the project in May 2006. Most of the fabrication of steam generators, pressure vessels and other equipment for both reactors was ready to install. This equipment was redeployed by KEPCO.

In October 2006 DPRK tested a nuclear weapon underground at Punggye-ri, 50 km northwest of Gilju/Kilju in the northeast of the country, and the whole matter was referred to the UN Security Council.

After several attempts at negotiation, in February 2007 agreement with DPRK was reached in the six-party talks involving China, Japan, Russia, South Korea and the USA. This involved DPRK agreeing to shut down and seal the Yongbyon reactor and related facilities including reprocessing plant within 60 days (by 14 April) and accepting IAEA monitoring of this, in return for assistance with its energy needs. Further assistance would follow the irreversible disabling of the reactor and all other nuclear facilities. The April 14 deadline was missed. After further diplomatic efforts, the reactor was shut down in mid July 2007 and an IAEA team was able to verify this and in addition, that other nuclear facilities at the site were also closed, notably the reprocessing plant ("Radiochemical Laboratory") and fuel fabrication plant. These were sealed and were to be subject to ongoing monitoring by IAEA. It was proposed to send the used fuel to Mayak in Russia or Sellafield in UK for reprocessing (required because the used fuel elements were chemically unstable). Any separated plutonium would not be repatriated.

The second phase of measures under the February 2007 agreement involved establishing a full inventory of nuclear materials and actually disabling the offending plants - initially promised by end of December 2007 but dragged out to June 2008 and then marked by demolition of Yongbyon's cooling tower. Phase 3 would be when North Korea hands over fissile materials and weapons gear. North Korea has raised the question of reviving the KEDO project for building a light water reactor.

In September 2008 North Korea refused to accept verification procedures and threatened to restart its Yongbyon reprocessing plant. The six parties met in December 2008 but did not reach agreement on verification, though removal of fuel rods from the Yongbyon reactor continued. Then North Korea expelled IAEA inspectors, restarted reprocessing at Yongbyon, and in May 2009 it exploded another nuclear device underground at Punggye-ri, possibly more successfully than 2006, with yield of about 2 kilotonnes TNT (cf Hiroshima 15 kt).

In February 2013 North Korea exploded a third nuclear device underground, with slightly higher yield than the earlier ones. It is not clear whether it used uranium or plutonium.

In May 2013 it appeared that the Yongbyon 25 MWt reactor was being prepared for recommissioning. A new cooling system for the reactor had been built and two tanks holding use fuel had been covered. Activity at the site continued. In September 2013 and early in 2014 there were indications that the reactor had restarted. In mid-2014 and again in January 2016 ISIS reported that it appeared to be operating, albeit not continuously and at reduced power.

In January 2016 DPRK evidently exploded a fourth nuclear device underground at or near Punggye-ri, claiming that it was a small hydrogen bomb.

In August 2016 the IAEA reported that DPRK had unloaded fuel from the Yongbyon reactor and reprocessed it. In that case up to 8 kg of plutonium could have been added to its supplies. ISIS estimates that in mid-2016 DPRK had about 13-21 nuclear weapons. In September a fifth underground nuclear explosion was announced and detected at Punggye-ri, more powerful than previous ones.

Uranium enrichment, research reactor

In October 2002 it emerged that DPRK had been working clandestinely to enrich uranium for weapons use, using centrifuge equipment. There appeared to be some linkage to Pakistan's centrifuge program and in 2005 Pakistan confirmed that its Khan network had supplied P2 centrifuges to DPRK in 1990s. The scope of this program remained unknown then, and in 2009 the official DPRK news agency announced that uranium enrichment tests had been carried out successfully and the process was in its final stage.

The question about uranium enrichment capacity was unresolved through these negotiations. In November 2010 it was confirmed that since 2008, some 2000 centrifuges had been set up in a building at Yongbyon, on the site of a fuel fabrication facility. The centrifuges appear to be Pakistani P2 types and their purpose is unknown, though North Korea says that they are producing only low-enriched uranium. Capacity was estimated at 8000 SWU/yr, capable of producing about 26 kg of weapons-grade uranium per year if applied to that end, but the capacity appears to have doubled to 16,000 SWU/yr in 2015. In January 2016 ISIS reported that the plant appeared to be operational.

North Korea has a small research reactor supplied by Russia at Yongbyon, the IRT, producing radioisotopes. It started in 1965 as a 2 MWt unit but has been uprated to 8 MWt. Originally it was fuelled with 10% enriched uranium, but then went to 36% and finally 80% with the uprates. Russia stopped supplying enriched uranium for this in 1990, and the imported fuel was used by 2011, according to ISIS. Prior to that there was some discussion about converting it to run on near 20%-enriched fuel, and this may have happened. It could be running on indigenous enriched fuel, which would require about 1000 SWU/yr of enrichment capacity. It was under IAEA safeguards, but is no longer.


Along with this, construction of a 25-30 MWe light water reactor at Yongbyon is reported to have begun in mid-2010, and to require fuel enriched to about 3.5%. Construction was well developed late in 2011, and apparently still incomplete in mid-2014. In January 2016 it appeared to be non-operational, and questions arose regarding what type of reactor it actually was.

In its September 2011 report, the IAEA notes that uranium hexafluoride found in a cylinder shipped to Libya by the Khan network in 2001 “very likely” originated in DPRK. The IAEA assesses that this indicates that North Korea had an undeclared uranium conversion capability prior to 2001.

The IAEA Director-General said in March 2014: "It will be five years next month since Agency inspectors were asked to leave the DPRK. Nevertheless, the Agency maintains its readiness to play an essential role in verifying the DPRK's nuclear programme. I call upon the DPRK to comply fully with its obligations under relevant Security Council resolutions, to cooperate promptly with the Agency in implementing its NPT Safeguards Agreement, and to resolve all outstanding issues."

See also DPRK section of IAEA website.


Iran attracted world attention in 2002 when previously undeclared nuclear facilities became the subject of IAEA inquiry. On investigation, the IAEA found inconsistencies in Iran's declarations to the Agency and raised questions as to whether Iran was in violation of its 1974 safeguards agreement, as a signatory of the NPT, which it joined in 1970.

Bushehr reactor

Iran joined the NPT in 1974 and in 1975-76 construction started on two 1293 MWe nuclear reactors comprising the Bushehr power station on the Persian Gulf. Siemens KWU was the contractor. After the Islamic revolution, payment was withheld and work was abandoned early in 1979 with unit 1 substantially complete. About the same time, Iran purchased 450 tonnes of uranium (531 t U3O8) from South Africa. Some 366 t of this was subsequently converted to UF6 at Esfahan.

In 1994 Russia was brought in to complete unit 1 as a VVER-1000 reactor. This necessitated major changes, including fabrication of all the reactor components in Russia under a construction contract with Atomstroyexport. The reactor eventually started up in May 2011 and was grid-connected in September, with commercial operation in 2013.

All fuel for the life of the reactor is being supplied from Russia, and it is intended that used fuel will be returned there, obviating the need for any fuel cycle facilities in Iran. All work has been under IAEA safeguards and operation is also under safeguards. The Atomic Energy Organisation of Iran (AEOI) has announced that feasibility studies for a further 5000 MWe have been ordered.

The 6-7 TWh/yr output from the first reactor frees up about 1.6 million tonnes (11 million barrels) of oil per year for export (or c 1800 million m3 of gas). In 2013 Iran’s Energy Minister said that it saved some $2 billion per year in oil and gas, so rapid payback of investment

Uranium enrichment

In connection with securing a supply of enriched fuel for its nuclear programme, in 1974 and 1977 Iran loaned $1.18 billion to the French Atomic Energy Commission to build the multinational Eurodif enrichment plant at Tricastin, and it took 10% equity in the enterprise (entitling it to 10% of output), which the Atomic Energy Organisation of Iran (AEOI) still holds. The loan was repaid with interest in 1991 but the plant has never delivered any enriched uranium to Iran. About 1991 Iran demanded delivery of its share of uranium under original contract, but this was refused by France due to political sanctions then being in force. Iran views this refusal as proof of the unreliability of outside nuclear supplies and uses the Eurodif episode to argue its case for achieving energy independence by supplying all of the elements of the nuclear fuel cycle itself. The 10.8 million SWU Eurodif plant operated by Areva started production in 1979 and closed in 2012. Iran has no equity in its successor.

In 2000 Iran declared its intention to build a uranium conversion plant (UCF) at the Esfahan Nuclear Technology Centre. At the same time it started building at Natanz a sophisticated enrichment plant, which it declared to IAEA after it was identified in 2002 by a dissident group. This is known as the Pilot Fuel Enrichment Plant (PFEP), but also at Natanz a large underground Fuel Enrichment Plant (FEP) was developed. Then traces of highly-enriched uranium were found at another facility connected with Natanz, the Kalaye Electric Co in Tehran. These traces were central to questions about Iran's compliance with its safeguards agreement. Questions about Iran’s intentions were further fuelled by discovery in 2009 of the underground Fordow enrichment plant (FFEP).

In 1991 Iran imported 1.8 tonnes of natural uranium from China. Iran did not declare this material however until 2002, and not all of it has been accounted for. Some was converted to metallic form – not required for any part of Iran's declared programme. The country has very small uranium reserves, apparently insufficient for any nuclear power programme.

Tehran Research Reactor

Iran has a 5 MW pool-type research reactor in Tehran which has operated since about 1967 and is monitored by the IAEA. Since being converted from 93% HEU about 1988 by Argentinian specialists, the Teheran Research Reactor (TRR) runs on 19.75% enriched uranium, and 116 kg of this was supplied from Argentina about 1993 - enough for 10-20 years depending on how the reactor is operated. This had nearly run out in 2009. The presence of molybdenum in Iranian UF6 means that domestic supplies may be unsuitable at this level of enrichment, but this is unconfirmed.

In 2009 it seemed likely that Russia might provide some further uranium for TRR fuel blended down from 36% enriched material and fabricated in France, in exchange for an equivalent amount of its own (< 5%) enriched uranium from Natanz. This was rejected by Iran, which then tabled a revised proposal. At issue was the amount of Iran's uranium stockpile to be handed over at one time. The international negotiators wanted to do this exchange in one large shipment, while Iran preferred several smaller swaps which maintained more of its overall holding for a longer period. In February 2010 the government ordered the AEOI to commence enriching Iranian uranium to 19.75%.

IR-40 heavy water reactor

Iran is also developing a 40 MW heavy water-moderated "research" reactor at Arak fuelled by natural uranium. It is declared as being to replace the old Teheran reactor. The IR-40 design is very similar to those used by India and Israel to make plutonium for nuclear weapons. Construction is under way and the incomplete plant was "inaugurated" in August 2006.

In July 2011 AEOI reported it as 75% complete. Iran has said that it will be under IAEA safeguards, and it has been subject to IAEA inspection during construction. However, in August 2012 the IAEA noted that “the lack of up-to-date information on the IR-40 Reactor is now having an adverse impact on the Agency’s ability to effectively verify the design of the facility and to implement an effective safeguards approach.” No design information for the IR-40 reactor had been provided since 2006. At May 2015 the plant had not been completed. Following UN acceptance of the Joint Comprehensive Plan of Action in July 2015, the Chinese foreign minister announced that China had undertaken to modify the Arak reactor and that to effect this “a joint working group consisting of the six parties and co-chaired by China and the United States will be set up.”

A heavy water production plant is operating at Arak, but the IAEA was denied access to it until December 2013.

Fuel fabrication

A fuel manufacturing plant (FMP) has been constructed at Isfahan to serve the IR-40 reactor and potentially Bushehr. To May 2015, 36 prototype and 11 final natural uranium fuel assemblies for IR-40 had been produced here, totaling 102 tonnes. Two fuel assemblies using 3.4% enriched uranium of mass 6 tonnes had also been produced.

The Fuel Plate Fabrication Plant (FPFP) at Esfahan converts near 20% enriched UF6 to U3O8 and makes fuel assemblies for TRR from these. Over 30 such fuel assemblies had been made to May 2015.

All the above facilities, except the Kalaye plant and the Arak heavy water plant, are under IAEA safeguards. Details are in the Director-General's reports to the IAEA board on the IAEA website.

International pressure

As an expression of international concern about all these facilities apart from Bushehr, the IAEA gave Iran until the end of October 2003 to resolve outstanding questions about them and its materials. In "a welcome and positive development", Iran then formally told the IAEA that it would accept the Additional Protocol to its safeguards agreement with IAEA, and that it would suspend all enrichment-related and reprocessing activities in Iran, specifically those at Natanz. However, implementation of measures in accordance with the Additional Protocol was suspended early in 2006, and enrichment resumed.

An IAEA report released to its member states in November 2003 showed that Iran had, in a series of contraventions of its safeguards agreement over 22 years, systematically concealed its development of key techniques which are capable of use for nuclear weapons. In particular, that uranium enrichment and plutonium separation from spent fuel were carried out on a laboratory scale. Iran admitted to the activities but said they were trivial.

In June 2004 The IAEA Board criticised Iran for failing to cooperate adequately with IAEA investigations of its nuclear program. Something of a stand-off then ensued until in August 2005 Iran announced that it would continue its endeavours to enrich uranium, despite international attempts to dissuade it, and the 200 t/yr conversion plant at Isfahan was started. However, the uranium feed from Iran's mines has significant levels of molybdenum and other contaminants which create difficulties for any enrichment, and particularly so for high enrichment. Estimates varied widely regarding what was required to overcome these problems, and the IAEA reports make no mention of them.

In August 2005 the IAEA Board called upon Iran to suspend work associated with uranium enrichment. In March 2006 the IAEA referred the issue to the UN Security Council. However Iran has not backed off from its uranium enrichment.

A Joint Plan of Action to curb Iran’s evident progress towards nuclear weapons capability was initiated on 24 November 2013 between Iran and the foreign ministers of China, France, Germany, Russia, UK, and USA (P5+1 – the five permanent members of the UN Security Council plus Germany) and a senior EU representative. It linked closely to the IAEA Joint Statement on a Framework for Cooperation signed two weeks earlier, and over the next 16 months proved effective in rolling back Iran’s nuclear program for the first time in a decade, applying innovative inspections measures, allowing only modest sanctions relief and keeping substantial pressure on Iran.

Enrichment ramp-up

Since about 2000 Iran’s uranium enrichment work has increased. Operations at the PFEP, FEP and the UCF are under international safeguards, though monitoring is constrained.

The IAEA 2003 report said that while no evidence of a weapons program had been found, it could not conclude that Iran's nuclear program was exclusively for peaceful purposes. In April 2006 it said that after three years of investigation and requests for information, the existing gaps in knowledge of Iran's nuclear program continued to be a matter of concern. The required "transparency and active cooperation by Iran" to enable the IAEA "to understand fully the twenty years of undeclared nuclear activities by Iran" were not forthcoming.

In March 2007 the Russian government told Iran that it would indefinitely withhold fuel for the almost-complete Bushehr nuclear power reactor unless Iran suspended its uranium enrichment program. Some Russian staff working on the project returned home. In the event, some 82 tonnes of fuel was delivered to Iran early in 2008. Fuel loading was expected late in 2009 but was deferred.

On 24 March 2007 the UN Security Council unanimously adopted a resolution imposing further sanctions on Iran and reaffirming that Iran must take the steps required by the IAEA Board, notably to suspend its uranium enrichment activities.

IAEA reports have described the situation through to 2015, and some details are in the information paper on Nuclear Power in Iran.

In June 2007 the IAEA Director General said: "Iran has not taken the steps called for by the Board nor responded to the demands of the Security Council. The facts on the ground indicate that Iran continues steadily to perfect its knowledge relevant to enrichment and to expand the capacity of its enrichment facility. Iran has also continued with the construction of its heavy water reactor at Arak. … This is taking place without the Agency being able to make any progress in its efforts to resolve outstanding issues relevant to the nature and scope of Iran´s nuclear programme, or being able to implement the Additional Protocol that would enable the verification of the absence of undeclared nuclear activities."

The Fordow site

In September 2009, when it learned that the matter was about to be exposed in the UN General Assembly, Iran told the IAEA that it was building another uranium enrichment plant, but gave no details. It is the Fordow plant, about 20 km north of Qom, in an underground tunnel complex on a military base. It is designed to have 16 cascades of about 3000 centrifuges and is reported to be under the control of AEOI. Evidently construction began in 2006 and it was expected to be operational in 2011. The IAEA first inspected it late in October 2009.

Clearly Iran played for time following the discovery in 2002 of its activities contravening its obligations under the NPT, and it developed its enrichment capacity to a high level meanwhile. The existence of the Fordow plant is particularly significant in that it would provide sufficient capacity to take a portion of the Natanz output of LEU up to weapons-grade.

The IAEA continued full involvement with Iran on nuclear safety issues, focused on Bushehr.

Enrichment to 20%, heightened concerns

The IAEA stated clearly in November 2007 that unless the Additional Protocol was ratified and in place it is not possible for the Agency to establish that undeclared nuclear materials and activities are absent. Its "knowledge about Iran's current nuclear program is diminishing." Meanwhile enrichment continued in defiance of UN Security Council resolutions.

The Iran situation has revived wider concerns about which countries should develop facilities with high proliferation significance – such as enrichment and reprocessing, even under safeguards, if there is no evident economic rationale. At some point in the future, such a country could give three months' notice of withdrawal from the NPT and reconfigure its facilities for weapons production. The USA asserts that Iran has been in fact developing just such a breakout capability.

This contention was supported in February 2010 when the government ordered the AEOI to commence enriching Iranian uranium to 19.75%, ostensibly for the Teheran Research Reactor (TRR), thereby significantly closing the gap between its normal low-enriched material and weapons-grade uranium. On 14 February 2010 about 1950 kg of low-enriched uranium (< 5%) from FEP was taken to PFEP, which would be enough for vastly more 19.8% enriched uranium than the TRR could conceivably use. AEOI has said that the TRR requires 1.5 kg of fresh fuel per month. International concern regarding the surge of activity in enrichment to about 20% U-235 is based on the fact that in terms of SWU (energy) input this is about 90% of the way to weapons-grade material, and thus would require only a small and possibly clandestine plant to bridge the gap.

At PFEP, two cascades are designated for production of LEU enriched up to 20% U-235, apparently for the TRR, and the balance of the plant is designated for R&D. One cascade enriches from 3.5% LEU to almost 20%, while the second one takes the tails from the first one and produces about 10% LEU with tails of less than 1% uranium. The enriched stream is fed into the first cascade. In total, some 1631 kg of 3.5% LEU from FEP was fed into one of these cascades, and 202 kg of 19.75% enriched uranium was produced at PFEP from the start of operations to January 2014 when enrichment to this level ceased under the Joint Plan of Action.

The IAEA earlier said that the PFEP operations now "required a full revision of the previous safeguards approach," including enhanced surveillance and checks. On 23 June 2011 the head of AEOI was quoted as saying: "We have the ability to produce 5 kg (of 20% enriched uranium) each month, but we do not rush." He had earlier said that the TRR required 1.5 kg of fuel per month. In August 2011 he confirmed that Iran had more 20% LEU than it needed for the Tehran research reactor, and that “security measures required that the sensitive part of the facilities would be transferred to underground buildings” – evidently Fordow. The IAEA reported then that monthly production rates of near 20 percent LEU had increased significantly, implying better performance of the two IR-1 cascades.

Over 2009-10 the Iranian centrifuge program was set back by the Stuxnet computer virus which affected Iranian companies involved with the control systems for the IR-1 centrifuges. In late 2009 to early 2010 about 1000 centrifuges at FEP were decommissioned. This appears to have been due to Stuxnet affecting frequency converters and causing the motors to over-speed, destroying the units. The normal failure rate of the IR-1 centrifuges is reported as about 10% per year.

The underground Fordow enrichment plant (FFEP) is evidently playing a larger role in producing 19.75% enriched uranium, using the well-proved IR-1 centrifuges. This positions Iran to stockpile a large amount of 19.75% LEU in a facility better protected against military strikes.

Between PFEP and FFEP Iran had produced 448 kg of 19.75% enriched uranium to January 2014, at over 15 kg/month. Of this, 337 kg (228 kgU) has been fed into conversion process at the Fuel Plate Fabrication Plant (FPFP) at Esfahan to produce 163 kgU as oxide (U3O8), and elsewhere 110 kg has been downblended to 5%. In May 2015 Iran had 228 kg of 19.75% enriched uranium, 61.5 kg as oxide powder, 44.9 kg as TRR fuel, and 121.2 kg as scrap, waste, or in-process, which created some concern for the IAEA.

In May 2014 the Enriched UO2 Powder Plant (EUPP) was commissioned. By May 2015, 6319 kg of natural UF6 (4262 kgU) had been converted to 1829 kgU as UO2, and 2720 kg UF6 enriched up to 5% (1835 kgU) had been converted to 151 kgU as UO2.

(Above paras are IAEA figures from May 2015 report, mass discrepancies unexplained.)

In June 2010 the AEOI announced that it planned to build four new research reactors for production of medical isotopes, including a 20 MW one to replace TRR when its operational life finishes in 15 years. This plan would justify production of more 20%-enriched uranium at Natanz, which gives rise to international concern.

Further concern was raised when Iran announced that it might build a nuclear-powered submarine, since this would potentially legitimize the country having high-enriched uranium for fuel. It was denounced internationally as simply an excuse for the production of weapons-grade uranium. The potential legitimacy arises from section 14 of the standard Comprehensive Safeguards Agreements signed by non-weapons states. This allows fuel for a “non-proscribed military activity” to evade safeguards.

International action from 2013

An agreement to curb Iran’s evident progress towards nuclear weapons capability was struck in November 2013 between Iran and the foreign ministers of China, France, Germany, Russia, UK, and USA (P5+1 – the five permanent members of the UN Security Council plus Germany) and a senior EU representative. It linked closely to the IAEA Joint Statement on a Framework for Cooperation signed two weeks earlier, and over the next 16 months proved effective in rolling back Iran’s nuclear programme for the first time in a decade, applying innovative inspections measures, allowing only modest sanctions relief and keeping substantial pressure on Iran.

In April 2015 a framework agreement was struck by the P5+1 group and Iran, taking forward the November 2013 interim Joint Plan of Action and forming the foundation upon which the final text of the Joint Comprehensive Plan of Action could be written by the end of June. It reflected the significant progress made in discussions between the P5+1, the European Union, and Iran, though it conferred some legitimacy to Iran’s enrichment programme.

In mid-July 2015 the Joint Comprehensive Plan of Action (JCPOA) with Iran was signed, after protracted negotiations. Iran agreed that over the next 15 years it will not enrich uranium above 3.67% and will reduce its stockpile of low-enriched uranium from 9000 to 300 kg of enriched uranium. Uranium research and development activities will only take place at Natanz, with much reduced number of centrifuges, while no enrichment will be carried out at the underground Fordow site. At Natanz, the number of installed centrifuges would be reduced from 19,500 to 6,100, only 5,000 of which will be spinning. All of them will be first-generation types: none of its more advanced models can be used for at least 10 years, and R&D into more efficient designs will have to be based on a plan submitted to the IAEA. In addition, Iran has agreed indefinitely not to build any new heavy water reactors or stockpile heavy water, and that the Arak reactor will be redesigned, with the original core being removed and destroyed. All used fuel will be shipped out of the country.

A separate agreement with the IAEA set out a path for “the clarification of past and present outstanding issues” regarding suspected nuclear weapons activities. Once the IAEA confirms that Iran has complied with its obligations under the international agreement, economic sanctions will progressively be lifted. The IAEA welcomed Iran's decision to implement the Additional Protocol to its Comprehensive Safeguards Agreement with the IAEA, allowing the intrusive monitoring required under the Joint Comprehensive Plan of Action (JCPOA).

In October the Iranian parliament approved a bill on the implementation of the JCPOA. Following this, all participants started to prepare for implementing their respective commitments, including lifting sanctions once the IAEA has verified that Iran had completed all its steps.

In mid-November 2015 the IAEA reported that a total of 4,112 IR-1 centrifuges and related infrastructure had been removed from service at the Natanz fuel enrichment plant along with 160 IR-2m centrifuges and related infrastructure. These centrifuges and other equipment are being stored at the site, under IAEA verification and monitoring. At the same time a total of 258 IR-1 centrifuges and related infrastructure were removed from the Fordow plant. In December 2015 Iran shipped more than 11 tonnes of various low-enriched uranium materials to Russia, in accordance with the JCPOA. The core of the Arak heavy water reactor was removed in January 2016 and concrete was poured into the calandria.

Implementation Day came in mid January-2016 when the IAEA verified that Iran had completed all of its nuclear commitments, the report of which was submitted to the IAEA Board and the UN Security Council. The effect of these actions is to increase Iran's 'breakout time' to obtain enough nuclear material for a weapon to one year, up from less than 90 days before the JCPOA. Iran must now start to implement provisionally the Additional Protocol to its IAEA safeguards agreement, which together with other measures under the JCPOA will increase the agency's ability to monitor nuclear activities in Iran and verify that they are peaceful.

See also WNA information paper on Iran, Iran section of the IAEA website, ISIS Nuclear Iran website, and Atomic Energy Organisation of Iran. Also IAEA media release July 2015.


The main thrust of Iraq's uranium enrichment program to 1991 was the development of technology for electromagnetic isotope separation (EMIS) of indigenous uranium. This uses the same principles as a mass spectrometer (albeit on a much larger scale). Ions of uranium-238 and uranium-235 are separated because they describe arcs of different radii when they move through a magnetic field. This process was used in the Manhattan Project to make the highly enriched uranium used in the Hiroshima bomb, but was abandoned soon afterwards.

The Iraqis did the basic research work at their nuclear research establishment at Tuwaitha, near Baghdad, and were building two full-scale facilities at Tarmiya and Ash Sharqat, north of Baghdad. However, when the war broke out in 1990, only a few separators had been installed at Tarmiya, and none at Ash Sharqat. They had accumulated some 550 tonnes of uranium oxide concentrate which was finally removed from Tuwaitha in 2008 and sold to Cameco. At least half of this originated in Niger about 1981.

The Iraqis were also very interested in centrifuge enrichment, and had been able to acquire some components including some carbon-fibre rotors, which they were at an early stage of testing.

In 1990 Iraq was clearly in violation of its NPT and safeguards obligations, and the IAEA Board of Governors ruled to that effect. The UN Security Council then ordered the IAEA to remove, destroy or render harmless Iraq's nuclear weapons capability. This was done by mid-1998, but Iraq then ceased all cooperation with the UN, so the IAEA withdrew from this work.

In 1981 Iraq's 40 MWt Osirak nuclear reactor was destroyed by an Israeli air strike just before fuel was first loaded into it. It was a French light-water materials test reactor using high-enriched uranium fuel, and Israel alleged that its purpose or at least potential was military.

Iraq joined the NPT in 1969, and its safeguards agreement with the IAEA was concluded in 1972.

South Africa

Another case of developing nuclear weapons was not under the NPT. Here, the state concerned had a nuclear power program producing nearly 10% of the country's electricity, whereas Iraq and North Korea only had research reactors. In addition to a 300,000 SWU/yr uranium enrichment plant at Valindaba which was set up to serve its nuclear power program during a time of trade sanctions, South Africa had a small finishing plant at Pelindaba which took a small proportion of the output and enriched it to weapons-grade.

In 1991, South Africa acceded to the NPT, concluded a comprehensive safeguards agreement with the IAEA, and submitted a report on its nuclear material subject to safeguards. However, the IAEA's initial verification task was complicated by the country's announcement that between 1979 and 1989 it built and then dismantled a number of nuclear weapons. In 1977 it was preparing to test the mechanism of such weapons in the Kalahari Desert, but was dissuaded following joint Russian and US aerial surveillance of the site. The IAEA was asked by South Africa to verify the conclusion of its weapons program.

In 1995 the IAEA was able to declare that it was satisfied all materials were accounted for and the weapons program had been terminated and dismantled.


Israel is one of three significant countries which have never been part of the NPT. Unlike India and Pakistan, Israel has no civil nuclear power program. However, in 1975 it concluded a limited safeguards agreement with the IAEA.

After Israel was established in 1948, there was close collaboration between France and Israel in nuclear research. Israeli scientists were involved with early French facilities near Marcoule.

In 1952 the Israel Atomic Energy Commission was established, and in 1955 the USA agreed to supply a 5 MWt pool-type reactor for Nahal Soreq, south of Tel Aviv. This IRR-1 required high-enriched uranium supplied from the USA. It started up in 1960 and from the outset was required to be under IAEA safeguards.

In 1957 an agreement was signed with France to build a large (24 MW thermal) heavy water research reactor at Dimona in the Negev desert. This would run on natural uranium and incidentally be suitable for producing weapons-grade plutonium. France apparently supplied four tonnes of heavy water for the reactor and also assisted in the construction of a reprocessing plant at the site.

In 1960 France reportedly urged Israel to put Dimona under full international safeguards, but this was not done. Due to US pressure, cursory twice-yearly inspections were carried out of the reactor only. The reactor started up in 1964, and with the benefit of oversize cooling circuits, power was subsequently raised to 70 MWt. A full suite of infrastructure is reportedly at the Dimona site, including fuel fabrication.

Uranium for the reactor was initially sourced from indigenous deposits, but most is believed to have come from South Africa, over some 20 years of nuclear collaboration from 1967.

In 1968 the US Central Intelligence Agency concluded that Israel had started producing nuclear weapons from separated plutonium. In 1974 it appeared to have 20 nuclear bombs, and by the late 1990s the estimate had grown to 75-130 nuclear warheads. No tests have been undertaken in Israel, but it is widely believed that Israel collaborated with South Africa in a 1979 test off the east coast there.

Israel has never confirmed or denied that it has nuclear weapons.

Using conventional weapons, an Israeli Air Force strike in 1981 destroyed Iraq's Osirak nuclear research reactor near Baghdad.


From about 2001 to 2007 Syria constructed a graphite-moderated gas-cooled nuclear reactor at Dair Alzour, a remote site on the Euphrates River, near Al Kibar. It was very similar to the plutonium production reactor at Yongbyon in North Korea, using natural uranium and graphite moderator. It was about 25 MWt and next to the reactor cavity had vaults for heat exchangers and spent fuel pond, but no turbine generator. The uranium came from indigenous phosphate deposits as by-product of treatment at Homs (Syria produces over 3.5 Mt/yr of rock phosphate which could yield 100-200 tU/yr).

Before fuel was loaded it was damaged beyond repair by an Israeli air strike in September 2007 and the remains were demolished and buried soon after. The entire enterprise, apparently aimed at production of weapons plutonium, was clandestine and in breach of Syria's obligations under the NPT. The evidence also pointed to North Korean involvement in supplying nuclear equipment. Syria claims that the building was a military non-nuclear installation, but has declined to discuss the matter with the IAEA in the light of evidence to the contrary, or to account credibly for the presence of anthropogenic (industrially-treated) uranium found at the site by IAEA in June 2008. It has refused to allow further IAEA access to this site or to a facility near Marj as Sulţān located in the eastern suburbs of Damascus, which was apparently connected with fuel preparation.

In its November 2010 report, the IAEA said that Syria's cooperation with the Agency had diminished, access was still denied to several sites in question, and there were several serious questions and issues outstanding. The IAEA called on Syria to sign and fully implement an Additional Protocol - supposedly in force from 2006 – as well as urgently remedying its non-compliance with its existing NPT safeguards agreement, concluded in 1980. In June 2011 the IAEA board resolved to report Syria to the UN Security Council and General Assembly over non-compliance with its safeguard obligations and failing to declare the construction of a nuclear reactor.


After several months of negotiations, Libya agreed in December 2003 to halt its development of nuclear weapons. For more than a decade it had been engaged in the development of a uranium enrichment capability, based on importing natural uranium together with centrifuge and conversion equipment, and the construction of now-dismantled pilot-scale centrifuge facilities. Some of these activities should have been reported to the IAEA under Libya's 1980 Safeguards Agreement with the UN body, but were not.

Evidently Libya's nuclear enrichment program was at an early stage and no industrial-scale facility had been built, nor any enriched uranium produced. Pakistan, which is not a party to the Nuclear Non-Proliferation Treaty, was the source of the illicit technology from the late 1990s.

In its September 2011 report on North Korea, the IAEA notes that uranium hexafluoride found in a cylinder shipped to Libya by the Khan network in 2001 “very likely” originated in DPRK.

Libya has a Russian 10 MW research reactor using 80% enriched fuel, which has been under IAEA safeguards. It has no nuclear power program. It asked the IAEA to verify publicly that all of its nuclear activities will henceforth be under safeguards and exclusively for peaceful purposes. In that regard, Libya agreed to take the necessary steps to conclude an Additional Protocol to its NPT Safeguards Agreement, and this came into force in 2006. This will provide the IAEA with broader inspection rights, and will require full transparency and active co-operation. The first IAEA inspections of previously-undeclared facilities were at the end of December 2003.


There have been persistent reports from defectors, opposition and dissident groups regarding certain technical developments in Burma which may indicate a program to develop a nuclear weapon. These are unconfirmed, and Burma formerly refused to cooperate with IAEA in any investigation, despite its safeguards agreement with IAEA having been concluded in 1995. However, in June 2011 the vice-president said that Myanmar “has halted [its nuclear research] programme as [the] international community may misunderstand Myanmar over the issue.” He said, “Myanmar made arrangements for nuclear research with the assistance of Russia in order that Myanmar will not lag behind other countries in that field and to improve its education and health sectors…,” but “Myanmar is [in] no position to take account of nuclear weapons and does not have enough economic strength to do so.” This statement was followed by the announcement that Myanmar has halted its nuclear research due to the high potential for international confusion. Then in November 2012 it announced that it would sign the Additional Protocol, and did so in September 2013. In mid-2013 the president reiterated the 2011 commitment. Concern had centred on North Korean involvement.

Main Sources:
Australian Safeguards & Non-proliferation Office, Euratom.
Bulletin of Atomic Scientists, March 2003, North Korea's nuclear program 2003.
Bulletin of Atomic Scientists Sep-Oct 2002.
Institute for Science and International Security (ISIS), Feb 2010, Iran's Gas Centrifuge program: Taking Stock
ISIS: Technical note on Burma, April 2011 and subsequent posts.

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