Louis Dugit-Gros, Visiting Fellow at The Washington Institute from 2021-23, is a French diplomat.
Threatening to reimpose old UN sanctions would likely have little practical effect on Tehran’s ability to trade oil and export drones, while the plethora of other potential complications suggest that it should be treated as a tool of last resort.
In recent weeks, the United States, Britain, France, and Germany have argued that Iran’s sale of drones to Russia for use against Ukraine violates UN Security Council Resolution 2231, the backbone of the Joint Comprehensive Plan of Action (JCPOA). These allegations, combined with ongoing diplomatic deadlock over reviving that 2015 nuclear agreement, have led some to suggest pursuing “snapback,” a provision that would reimpose terminated UN resolutions on Iran and essentially scrub the JCPOA from the books. How would snapback work, and what political, economic, and security consequences would it have?
How It Works
The relevant provision in Resolution 2231 was designed to allow rapid resumption of UN sanctions on Iran in case of “significant non-performance of commitments under the JCPOA.” Any “participant state” can trigger snapback. Although the text does not precisely define what constitutes “significant non-performance,” it does indicate that only violations of the nuclear deal itself are grounds to trigger snapback—as opposed to issues covered under Resolution 2231 that are not in the JCPOA, such as prohibitions on exporting weapons like the drones recently sent to Russia (see below). That said, Iran’s repeated violations of its nuclear commitments provide ample justification on their own for triggering snapback. Whatever the reason for disagreements between parties to the JCPOA, the resolution encourages states to resolve them via the deal’s dispute resolution mechanism before resorting to snapback.
The snapback process is designed to avoid the need for consensus among the five permanent members of the Security Council (the United States, Britain, China, France, and Russia). Once the measure is triggered—namely, by one or more JCPOA participants lodging a formal complaint regarding alleged violations—Iran’s relief from UN sanctions would expire within thirty days unless the council passes a resolution to continue it. And any permanent member can veto said relief resolution, making snapback difficult to halt except by the parties that triggered it (though as will be discussed below, the U.S. decision to withdraw from the JCPOA complicates its potential role in this process). The snapback mechanism itself expires in October 2025.
Snapback would bring into force six previous Iran-related Security Council resolutions: 1696 (2006), 1737 (2006), 1747 (2007), 1803 (2008), 1835 (2008), and 1929 (2010). The specific effects would include reinstating the expired UN arms embargo that barred countries from supplying, selling, or transferring most combat equipment to Iran and prohibited Tehran from exporting any weapons. In addition, it would rescind the October 2023 expiration for provisions that bar Tehran from exporting missiles and drones or conducting “any activity” related to ballistic missiles “designed to be capable of delivering nuclear weapons” (for details on the drone provisions, see the “Ukraine weapons transfers” subsection below).
The snapped-back resolutions would also impose export controls, travel bans, asset freezes, and other restrictions on individuals, entities, and banks involved in certain Iranian nuclear and missile activities. Moreover, national governments and the European Union would be required to incorporate these designations into their laws. Finally, most of Iran’s nuclear activity, including what it was permitted to conduct under the JCPOA, would once again be prohibited.
Snapback, Round One
When the Trump administration withdrew from the JCPOA in 2018, it did not try to trigger snapback. At the time, international inspectors affirmed that Iran remained within its nuclear limits, and U.S. officials may have been concerned that snapback would detract from their effort to make a clean break from the deal and potentially undermine Washington’s veto power on the Security Council over the longer term.
Two years later, however, the administration launched a controversial effort to trigger snapback despite no longer being party to the JCPOA. In June 2020, with a presidential election approaching and the arms embargo set to expire that October, U.S. officials disseminated a draft proposal to extend the embargo. The idea found little support from Britain, France, and Germany (aka the E3), who emphasized their preference for fully preserving the JCPOA despite the challenges caused by America’s withdrawal and Iran’s multiple violations. China and Russia also opposed it.
The Trump administration then attempted to trigger snapback that August by citing Iran’s noncompliance with the JCPOA, asserting that the United States was still a “participant” in the agreement according to the definition set out in Resolution 2231. Thirteen of fifteen Security Council members, including the E3, rejected this interpretation, and the Biden administration later withdrew it in February 2021. The failure of this effort underscores that Washington cannot trigger snapback unilaterally—any such move would have to be taken by, and likely in close concert with, the E3.
Considerations for Triggering Snapback
Snapback is not a mechanism to be used lightly or as a lever to improve the West’s negotiating position. This is not so much because of its potential economic consequences, which are limited. Rather, snapback is effectively the emergency stop button for nuclear negotiations, and triggering it would be taken as a definitive sign that talks had failed. Hence, it should be used only when Western governments conclude that returning to the JCPOA is impossible, and after closely considering the following ramifications:
Nuclear diplomacy. Implementing snapback would return nuclear diplomacy to “factory settings,” essentially erasing the compromises embedded in the JCPOA and efforts to revive it. The reimposed UN resolutions would require Iran to “suspend all reprocessing, heavy water-related, and enrichment-related activities”—a restriction that Tehran has defied from the start and would defy again, this time with a more advanced enrichment program in place.
Theoretically, a snapback reset might facilitate new talks toward a better deal in the future. More likely, though, it would close the door to any negotiations for a significant period of time, and if new talks were initiated, the process would probably be very long, perhaps comparable to the many years of effort that led to the JCPOA.
Alternatively, Western governments may hope to use the mere threat of snapback as negotiating leverage. For example, the E3 could trigger the thirty-day snapback process and demand that Iran back off of its hardline negotiating position before that deadline arrives. But this is unlikely to be effective given that the economic consequences of snapback are not very significant (see below), while the threat itself would probably extinguish any remaining Iranian interest in a deal.
Sanctions pressure. If sanctions were snapped back, the resultant economic impact on Iran would likely be marginal, since Tehran already faces an array of U.S. secondary sanctions that are far more comprehensive and damaging than what is outlined in past Security Council resolutions. For example, none of the relevant resolutions would curtail Iran’s oil or non-oil trade. Although states would have to require companies and banks to “exercise vigilance” when dealing with entities incorporated in Iran, any such firms that are already willing to risk U.S. sanctions probably would not be deterred by this UN requirement.
On the energy front, snapback is unlikely to dissuade China from buying hundreds of thousands of barrels per day of Iranian crude, which is imported through a complex, clandestine system in the Middle East and Southeast Asia to conceal its origin. Symbolically ending the JCPOA talks could induce some caution among businesses in transit countries such as Turkey and the United Arab Emirates, which may have been betting that sanctions will soon be lifted. Yet beyond a period of adjustment, the lasting impact would probably be limited, as many neighboring governments would remain reluctant to crack down on sanctions evasion.
For countries already adhering to U.S. restrictions, snapback would reinforce their policy orientation. For example, the prospect that South Korea might unfreeze Iranian funds held in its banks would disappear indefinitely. Yet snapback would not automatically restore the most significant sanctions imposed by the European Union a decade ago—restrictions on energy, minerals, chemicals, transport, and the financial sector would require unanimous approval in Brussels.
The most significant economic impact would probably be symbolic. By demonstrating that there is no prospect for reviving the JCPOA, snapback could fuel additional turbulence in Iranian markets, further dry up domestic investment, and spur additional capital outflows as Iranians grapple with the indefinite reality of severe sanctions. While sticking to a hard line in recent negotiations, Iranian officials have frequently tried to placate their domestic audience with the prospect that funds will soon be unfrozen, likely in part to keep the glimmer of a deal alive and strengthen the rial. Yet snapback would end that illusion.
Ukraine weapons transfers. At this stage, snapback is unlikely to strengthen efforts to curtail Iranian weapons transfers to Russia for use in Ukraine. These deliveries already violate paragraphs 4 and 6, Annex B, of Resolution 2231, which restricts the transfer of certain equipment under the Missile Technology Control Regime (MTCR) without prior Security Council approval and bans financial interactions with designated entities. Reimposing the resolution’s broader arms embargo would create an additional justification for why the drone transfers constitute a violation, but without giving policymakers any additional tools for deterring them.
In the longer term, the October 2023 expiration of the missile testing and MTCR provisions may provide a more useful deadline for policymakers. That is, if a deal to revive the JCPOA is not reached or abandoned by then, using snapback to prevent the expiration of these provisions may make sense.
Iran’s response. Tehran’s reaction to snapback would depend in part on the message it receives from Russia and China. If they ask the regime to stay within certain guardrails—for instance, by avoiding efforts to advance its weaponization program, expel inspectors, or withdraw from the Nuclear Nonproliferation Treaty—then Iran’s response might be moderate. Yet the extent to which they would try to constrain the regime is unclear. China has been largely unwilling to lean on Iran during the JCPOA negotiations and has extended a financial lifeline by purchasing its oil in defiance of U.S. sanctions. And Russia’s deepening security and strategic ties with Tehran may reduce its willingness to play any constructive role.
Ultimately, Iran’s reaction would aim to demonstrate resistance and resilience, whether through nuclear steps, conventional steps, or both. Nuclear steps could include further restricting inspections and enriching uranium to 90 percent (i.e., the commonly accepted threshold for weapons-grade material). Conventional steps might take the form of destabilizing attacks or vessel seizures in the Strait of Hormuz, as well as escalation by proxies in Iraq, Lebanon, Syria, and/or Yemen.
Henry Rome is a senior fellow at The Washington Institute. Louis Dugit-Gros is a visiting fellow with the Institute and a diplomat with the French Ministry for Europe and Foreign Affairs; the views expressed herein are strictly personal.