Snapback: Iran's Nuclear Programme and Crisis of Legitimacy

Over the weekend, UN Security Council sanctions on Iran – which had been lifted under the 2015 Joint Comprehensive Plan of Action (JCPOA) – were reinstated. This comes on the back of long-standing Iranian violations of the nuclear deal and continued failures to cooperate with the International Atomic Energy Agency (IAEA) in providing transparency of its nuclear activities. Iran has, in turn, been threatening to withdraw from the Nuclear Non-Proliferation Treaty (NPT) should UNSC sanctions return.

While all of this has direct implications for the Iranian nuclear programme, snapback has also shone a floodlight on – and contributed to – the broader crisis of legitimacy facing international institutions and the global non-proliferation regime. The latter, rather than the specifics of what happens next on the Iran nuclear file, may prove to be the most long-lasting fallout of UNSC snapback.

What are the Material Implications of Snapback?

In broad strokes, pre-2015 UNSC sanctions on Iran included an arms embargo, bans on transfers of nuclear and missile technology, as well as some restrictions and calls for vigilance in conducting financial dealings and offering financial services to Iran, as well as requirements for Member States to inspect Iranian ships and aircraft suspected of violating these provisions. The UNSC restrictions also included targeted financial sanctions (TFS) – a list of individuals and entities believed to be contributing to Iran’s nuclear and missile programmes. The ‘snap-back’ reinstates these sanctions provisions, as well as certain European Union sanctions.

Establishing the material impact that ‘snapback’ will have on the Iranian economy is difficult. The bulk of the economic pressure on Iran comes from US unilateral sanctions and – to a lesser degree – unilateral and multilateral sanctions from the EU, the UK and a number of other states. The US had infamously already reimposed nuclear related sanctions on Iran in 2018, when the first Trump Administration withdrew from the JCPOA. This had a cooling effect on the willingness of businesses and financial institutions globally to engage with Iran, so as not to run afoul of the US Treasury. This already wide-spread and long-standing reticence of countries and businesses around the world to do business with Iran will limit, though not entirely negate, the practical impact of further UN sanctions.

Critically, multilateral sanctions are only as strong as their weakest link. UNSC sanctions should therefore be the golden standard, as all member states are required to comply with UNSC decisions. In practice, however, the current fragmented state of the international community and the colossal split between the five permanent members of the UNSC has undermined this unity of action. Russia and China have contested the legitimacy and legality of snapback. It is therefore safe to assume that Moscow and Beijing will likely refuse to comply with the reinstated sanctions. This will in turn grant permission to other players – including states who have historically served as important facilitators for legitimate and illicit Iranian trade – to also disregard them.

Snapback is also intended to serve as a diplomatic slap on the wrist for Iran – a multilateral condemnation of the threat to international security posed by Iran’s nuclear activities and persistent failure to address related concerns. The lack of unity among the P5 in delivering that message will only serve to reinforce to Iran – and those who may look to help Tehran circumvent sanctions – that it has powerful friends in its corner who are willing to shelter it from accountability. All of this will seriously undermine the material impact of snapback.

The Bigger Picture

Yet the most important and long-lasting implications of Russian, Chinese and Iranian reactions to snapback go well beyond the immediate question of holding Iran accountable for its concerning nuclear activities. While a debate can and should be had over whether sanctions on Iran should have been snapped back (this author has previously argued in favour), the E3 were fully within their right to trigger the snapback mechanism. That right was negotiated and agreed to by the E3, Iran, China and Russia under the JCPOA and enshrined in UNSCR 2231. The decision by Russia and China – two permanent members of the Council – to argue against the legality of UNSC sanctions is a new low for the legitimacy of the UNSC sanctions mechanism and the work of the Council more broadly.

UNSC decisions have always been notoriously challenging to enforce and compliance with UNSC sanctions on North Korea and Iran – including by Russia and China – has always been spotty, even at the best of times. Russian and Chinese nationals, companies, banks and vessels have long facilitated North Korean circumvention of sanctions. Since the start of its full-scale invasion of Ukraine, Moscow appears to have outright ignored restrictions on trade in arms with North Korea. Politicisation of the UNSC is also not novel. Instances where the P5 have wielded their veto to impose their interests on the Council are ample. Most recently, the United States has been widely criticised for repeatedly vetoing UNSC resolutions demanding a permanent ceasefire in Gaza, despite otherwise unanimous support from the rest of the Council.

However, outright refusal to accept the outcome of a UNSC vote by members of the P5 is – as far as the author can ascertain – unprecedented and will do irreparable damage to the legitimacy of the Council and its decisions going forward.

States have, of course, previously elected not to seek a UNSC decision on a contentious issue rather than risk getting an unfavourable outcome and placing themselves in a position to have to go against it or to contest its legitimacy; the 2003 US invasion of Iraq is perhaps the most infamous example. Israeli and US attacks on Iran’s nuclear sites in June, should, arguably also have been put to a UNSC vote to assess whether they met the criteria for the use of force in self-defence. Admittedly, Russia and China had attempted to leverage the UNSC mechanism to forestall the return of sanctions on Iran by tabling a resolution for the extension of snapback. The attempt was, however, ultimately voted down.

This leads to a broader question on the future of international institutions and frameworks. Do they still matter and does membership in itself carry intrinsic value? Or is it still possible and meaningful to try and enforce compliance? And what does all this mean for the future of the Iran nuclear programme and the broader non-proliferation regime?

Iran and the NPT: Is Just Showing Up Enough?

This question is at the heart of what will come next in the saga of the Iranian nuclear programme: the future of Iran in the NPT.

Senior voices in Tehran have repeatedly threatened to withdraw Iran from the NPT if UNSC sanctions were snapped back, or to at least give notice of an intention to withdraw. The debate inside Iran of whether to pull Iran out of the NPT has intensified since the E3 triggered the snapback mechanism in August. Draft Iranian legislation to withdraw from the NPT has reportedly been finalised and is ready to be put to a vote in the Iranian parliament. Nevertheless, it does not appear that a decision to withdraw from the NPT has been made – one that would most likely come from the Supreme National Security Council and – ultimately – the Supreme Leader, rather than any parliamentary effort. Some among Iran’s senior leadership have also downplayed the implications of UNSC snapback and continued stressing the viability and necessity of pursuing diplomacy, even after the E3 triggered the snapback mechanism.

Yet, it remains unclear whether an Iranian decision to withdraw or remain in the NPT will deal the greater blow to the Treaty and – by extension – the global non-proliferation regime. Just as disregarding UNSC decisions, or choosing not to seek them at all, both undermine the credibility and effectiveness of the Council in different ways.

While Iran remains party to the NPT and its Comprehensive Safeguards Agreement (CSA) with the IAEA remains in place, the country has been failing to meet its CSA obligation. Tehran has long failed to address outstanding IAEA questions about certain activities and facilities in its nuclear programme, which is what led to the adoption by the IAEA Board of Governors in June of a resolution finding Iran in non-compliance with its CSA obligations. Following the Israeli and US military strikes on Iran’s nuclear facilities later that month, Iran denied IAEA access to its nuclear facilities and has failed to provide information on the state and whereabouts of its highly-enriched uranium stocks. Some inspections reportedly resumed after an agreement was reached between Iran and the IAEA earlier this month but Iran appears determined that any cooperation with the IAEA – if it continues at all – would be on Iran’s terms. Such a negotiated approach is not in line with the obligations that Iran remains bound to under its CSA.

Furthermore, the advanced state of the Iranian nuclear programme prior to the military strikes, its accumulation of extensive stockpiles of highly-enriched uranium with no plausible civilian justification, its historical – and possibly more recent – engagement in activities with weaponisation relevance, as well as repeated threats from senior Iranian experts and policy-makers to consider the pursuit of a nuclear weapons capability go against the spirit – if not exactly the letter – of the NPT.

Iran’s reticence to cooperate on granting transparency over its nuclear programme is perhaps understandable in light of the Israeli and US attacks. However, allowing the IAEA to conduct inspections at all declared sites is not optional under Iran’s CSA. Should Iran be allowed to negotiate on its own terms over what aspects of its CSA it will abide by and which it can disregard, this would set a dangerous precedent for other states who may wish to do the same in the future. It would place Iran in a class of its own among non-nuclear weapons states party to the NPT and would open the door to the possibility of entertaining other ‘exceptional’ cases in the future. This would seriously undermine the importance and credibility of the IAEA and its safeguards work.

A more flexible option for safeguards does exist, in the form of the INFCIRC/66-type agreements. These have been used by Israel, India and Pakistan – states not party to the NPT. A similar arrangement would presumably be available to Iran, should it decide to withdraw. But it would also then have to be willing to accept the consequences of withdrawal – which may include further economic and diplomatic ostracisation or military strikes.

Tehran should not necessarily look to the experiences of India, Pakistan and Israel for what awaits it should it decide to withdraw from the Treaty; the historic, military and political contexts are too different. North Korea may be a better point of reference and should serve as a cautionary tale. While Iran has greater diplomatic and economic relationships in its region and globally than North Korea did when it decided to withdraw from the NPT, Israel and the US have shown themselves both able and willing to expend significant military force and diplomatic and economic leverage to prevent the emergence of a nuclear-armed Iran. Other states, including those in Iran’s neighbourhood which continue to maintain economic relations with Iran, may also choose to isolate the Islamic Republic, considering the threat to their own security that a nuclear armed Iran would pose.

Conclusions

As such, active efforts to bolster the nuclear non-proliferation regime will be required regardless of whether Iran decides to withdraw from the NPT in response to snapback, give notice of an intention to withdraw or remain a party to the Treaty. These efforts must focus on reinforcing the continued value not just of the NPT and the IAEA but of full compliance with both the spirit and the word of the NPT and CSA obligations – both in the Iran context and for the future of the global non-proliferation regime more broadly.

To that end, should Iran decide to remain a party to the Treaty, it cannot be allowed to construct a bespoke safeguards regime for itself. While allowing Iran to negotiate limited and ad hoc access by the IAEA may seem better than complete opacity of the programme, such an approach would not fully address proliferation concerns in relation to the Iranian programme and would damage the broader non-proliferation regime. Securing a full return of IAEA inspectors to all sites that are subject to CSA inspections must remain the ultimate and urgent objective – both as a priority for maintaining visibility of the Iranian nuclear programme and because doing otherwise risks undermining broader non-proliferation efforts.

At the same time, the consequences of NPT withdrawal must also be made clear to Iran. This will necessarily have to include economic and diplomatic pressure from Iran’s allies, who may yet need convincing over the threat posed by a nuclear armed Iran. This, in turn, points to the need to address systemic challenges plaguing UNSC sanctions enforcement or to accept that they are no longer fit for purpose and seek alternative solutions. Is there still a way of convincing the majority of UN member states of the importance of complying with UNSC sanctions and decisions? Or are unilateral enforcement and coercive mechanisms the only real game left in town?

The answers to these questions will have repercussions well outside of the Iran nuclear programme.

© RUSI, 2025.

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