The Iran Deal: the 25-year Road from Vienna

The Iranian nuclear deal agreed in Vienna may be one of the most important post-Cold War diplomatic accords. But it is important to understand how it evolves over the coming decades.

The Road to Vienna

On Tuesday morning, one of the most important diplomatic accords of the post-Cold War period was signed in Vienna. The Iranian nuclear dispute has festered for thirteen years. This week’s deal – the Joint Comprehensive Plan of Action (JCPOA), a 160-page document with five annexes – builds on landmark agreements in Geneva in 2013 and Lausanne in April.

Without rehearsing its strengths and weaknesses, the most important feature is that Iran’s nuclear programme will be limited and monitored such that, over the next two decades or so, any Iranian efforts to construct a nuclear weapon – whether in secret or in declared facilities – will not only be detected swiftly, but in ample time for the United States and its allies to craft a diplomatic and, if necessary, military response. Iran will be rewarded with sanctions relief only when it has imposed these restrictions and, if disputes arise, any of the E3+3 can - after an admittedly complex process of adjudication and arbitration - re-impose sanctions by notifying the UN Security Council.

The Road Ahead

However, this is a fluid deal that changes shape over time. In particular, the restrictions on Iran progressively fall always. This analysis sets out how things will look at different stages, though it does not seek to be exhaustive.

The JCPOA will first be sent to the UN Security Council for endorsement, ‘in the coming days‘. 90 days after that is ‘Adoption Day’, i.e., some time in October 2015, from which the various stages below are measured. Meanwhile, Iran is expected to have cooperated adequately with the IAEA sufficiently to allow the Agency to resolve concerns about Iran’s past weapons-related activity (known as Possible Military Dimensions, or PMDs) by December 2015. This is a remarkably ambitious deadline, as the process is not merely technocratic. Even once the IAEA makes its judgment, the E3+3 must submit a resolution to the Agency’s Board of Governors ‘with a view to closing the issue’. If Iran fails to cooperate or one of the E3+3 take issue with the IAEA’s criteria for absolving Iran, the deal could fall apart at this early stage. Assuming this does not occur, the deal then unfolds as below.

  • 2020: five years into the deal, the UN arms embargo on Iran will be removed (this is only alluded to in the text, but widely reported), with the exception of ballistic missiles. China and Russia were the principal arms suppliers to Iran before the onset of the embargo, and may resume sales - although Moscow has indicated that the embargo never affected ‘defensive’ systems including air defense systems, in the first place. Given that Russia and China both demanded a removal of the embargo from day one, the five-year delay is a reasonable achievement for the Western powers in the E3+3.
  • 2023: eight years in,[1] the EU will terminate its proliferation-related sanctions and the US will legislate the removal of its own sanctions. The UN embargo provisions on ballistic missiles will also lapse. However, Western intelligence agencies will likely continue to disrupt Iran’s supply chain for missiles, and other control regimes like the Missile Technology Control Regime (MTCR) will continue to limit the flow of missile-relevant technologies to Iran. Later that year, eight and a half years in, Iran will be able to start manufacturing more advanced and therefore efficient IR-6 and IR-8 centrifuges. However, it can only produce up up to 200 per year of each type, ‘without rotors’, and only test up to 30.
  • 2025: a decade in, the UN Security Council will terminate the JCPOA and close the nuclear file. This is a key moment in the deal’s evolution. At this point, Iran can add to its 5,060 centrifuges at Natanz – albeit, as explained below, ‘at a reasonable pace’. It can also start manufacturing complete IR-6 and IR-8s, at the same rate as earlier, though it still has to store them above ground at Natanz, rendering them vulnerable to airstrikes.
  • 2030: fifteen years in, Iran will be free most of the core restrictions. Three are notable. First, it will be able to perform research and enrich uranium outside of Natanz, including at the underground Fordow or in newly-built facilities, and enrich uranium beyond 3.67% to levels that would bring it much closer to weapons-grade. However, it would still have to tell the IAEA as soon as it intends to build a new facility - and if it doesn’t do so, the IAEA would still be able to see the diversion of uranium or centrifuge parts. Second, Iran can at this point allow its stockpile of uranium to rise above 300kg, which would also shorten the overall breakout time. Third, Iran could build additional heavy water reactors, keep excess heavy water in the country rather than sell it, and – though the language is abstruse, and Iran says it doesn’t intend to do so – reprocess spent fuel from reactors and separate plutonium from. Fourth, the IAEA’s rights of ‘continuous monitoring’ of centrifuges in storage and ‘daily access’ to Natanz also lapse at this point, though inspectors will still have other types of access.
  • 2035 and beyond: Iran will no longer have to accept IAEA monitoring of centrifuge rotors and bellows after 20 years. Five years later, the IAEA’s oversight of uranium ore concentrate will also lapse. Both of these things will make it much harder to detect covert enrichment activity.

The Post-2030 Environment

It is important to note that the JCPOA does place other constraining obligations on Iran that constrain it even as the formal restrictions fall away. In particular, the deal states: ‘the initial mutually determined limitations described in this JCPOA will be followed by a gradual evolution, at a reasonable pace, of Iran’s peaceful nuclear programme, including its enrichment activities, to a commercial programme for exclusively peaceful purposes’.

As part of this, Iran will have to submit a ‘long-term enrichment and enrichment R&D plan’ as part of its initial declaration under the Additional Protocol. Iran would therefore have to justify a post-2030 expansion of its enrichment by pointing to concrete needs, such as planned reactors. These needs are likely to remain limited, given that Iran is unlikely to be able to afford or secure foreign investment in a large-scale energy programme of the sort it has envisioned in the past - as with Ayatollah Khamenei’s remarks last summer that he sought enrichment capacity of 190,000 SWU, or approximately 190,000-243,000 first-generation centrifuges. If Iran expands capacity by pointing to future but as-yet hypothetical requirements, and these appear implausible, this could trigger a serious dispute over what constitutes a ‘reasonable pace’. A great deal will therefore depend on how Iran exercises its rights under the JCPOA.

Iran’s own decisions, as well as its rivals’ interpretations and responses, will depend on a variety of factors. One factor is the evolution of Iran’s regime, and the balance of power between pragmatists and hardliners. But while a more open and democratic Iran would ease concerns about future enrichment, there is little evidence that is a probable scenario.

A second factor is the process by which the IAEA issues a judgment about PMDs. As a senior US administration official put it in a background briefing, ‘we also hope that it will be a different situation in terms of confidence in their program and where they're going’. If the IAEA is perceived to have uncovered the full extent of past Iranian transgressions, this will ease concerns; conversely, if this process is perceived as rushed, incomplete, or inadequate, then these concerns will be greater.

A third factor will be the regional security environment, including Iran’s policies in the Levant and the Persian Gulf, and the degree of competition between Iran and Saudi Arabia. If competition continues at its present level, Saudi Arabian nuclear hedging - already underway - may expand and intensify, although Saudi signaling should certainly not be taken at face value. If Syria and Iraq remain highly unstable into the next decade, Iranian support for the Assad regime (or future remnants thereof), Hezbollah, and/or Shia militias could even deepen Western concern over Iran’s regional role. If Iran were then to expand nuclear activities, even without the shadow of PMDs, this could result in new tensions.

This pessimistic tone should be tempered, finally, with the reminder that a region without the JCPOA would, in likelihood, be more uncertain and dangerous than one with it, and that the nuclear deal agreed in Vienna is, in large part, a significant accomplishment.



1. There is a possibility that it could come sooner, if the IAEA issues a so-called Broader Conclusion, though this typically takes a long time and would not apply to the centrifuge restrictions.


Shashank Joshi

Advisory Board

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