FAQ: Time Is Short to Trigger the Iran Nuclear Deal’s Snapback Mechanism

It is long past time to reimpose the UN sanctions on Iran.

In 2015, the United States, France, Germany, the United Kingdom, the European Union, Russia, and China reached a nuclear deal with Iran — formally known as the Joint Comprehensive Plan of Action (JCPOA) — that suspended UN sanctions on Tehran. The deal and its associated UN Security Council Resolution (UNSCR) 2231 included a mechanism known as “snapback” for one JCPOA party to reimpose sanctions within roughly 30 days should Iran engage in “significant non-performance” with the agreement.

UN sanctions in Resolutions 1696 (2006), 1737 (2006), 1747 (2007), 1803 (2008), and 1929 (2010) remain in limbo despite Iran’s prolonged non-compliance with the JCPOA and Iran’s statement in 2020 that it would no longer observe the deal’s terms, compounded by the accord’s largely defunct status since Washington’s withdrawal in 2018. However, UNSCR 2231 remains in force, and time is short to act because the resolution, the UN sanctions, and their snapback mechanism all expire on October 18, 2025. This unique mechanism, which bypasses a Russian or Chinese veto, represents the last opportunity to maintain and restore global sanctions on Iran.

The United States, plus France, Germany, and the United Kingdom — collectively known as the E3 — reportedly agreed on July 14 that the E3, as remaining JCPOA parties, will trigger snapback by the end of August if Iran does not agree to new limits on its nuclear activities. France’s foreign minister underscored that the parties would be “justified in reapplying global embargoes on arms, banks, and nuclear equipment that were lifted 10 years ago” absent “a firm, tangible, and verifiable commitment from Iran.”

Q: Why is retaining the sanctions critical to nuclear nonproliferation in Iran?

UN sanctions on Iran impose multilateral trade restrictions and key prohibitions on Iran’s nuclear proliferation activities.

• Despite U.S. and Israeli strikes against Iran’s key nuclear facilities, which severely set back the regime’s atomic weapons option, Tehran will likely try to reconstitute its nuclear program by procuring equipment and materiel from abroad.

• If UN sanctions sunset in October 2025, Iran will no longer face a global ban among 190+ countries on procuring nuclear and nuclear-related equipment.

The UN resolutions also require Iran to stop enriching uranium and reprocessing plutonium indefinitely, adhere to a strong nuclear inspection agreement called the Additional Protocol, and cooperate with the International Atomic Energy Agency to assure its nuclear program is devoted to peaceful uses.

• Such provisions lay the basis for any durable, future nuclear deal with Iran that prevents its development of nuclear weapons.

• Snapback provides an opportunity for Washington to definitively bring European countries back in line with the original U.S. and European standard of no uranium enrichment in Iran.

Q: What missile and military restrictions would snapback reimpose?

Along with addressing nuclear trade, snapback would restore military and missile embargoes on Iran that lapsed under UNSCR 2231 in 2020 and 2023, respectively, as well as a prohibition on launching missiles.

• The embargoes prohibited Iran’s provision of arms, drones, and missiles, for example, both to Russia and to terrorist proxies seeking to attack Israel, U.S. troops, and Gulf partners in the Middle East.

• Prohibiting, for example, key exports of missile materiel from China to Iran can stymie Iran’s efforts to rebuild its missile arsenal for use against Israel.

• Outlawing missile testing provides a legal basis for stopping Iran from advancing its program for intercontinental nuclear-capable ballistic missiles that will one day be able to hit the United States.

Q: How would snapback reimpose other UNSC sanctions passed between 2006 and 2010 containing key restrictions on Iran?

• The resolutions authorized states to inspect Iranian cargoes suspected of containing prohibited items, laying the basis for international efforts to interdict and seize them.

• The resolutions designated Iranian entities and officials engaged in proliferation activities and required countries to halt proliferation financing for Iran, implement travel bans against designated Iranian officials, and freeze the designated officials’ and entities’ assets.

• The resolutions, in particular, restricted financial transactions with Iranian banks, including the Central Bank of Iran, if linked to proliferation activities. They urged states to prohibit new banking relationships with Iran and monitor Iranian financial institutions.

• The resolutions called for global vigilance in providing loans or credits to Iran, except for humanitarian or development purposes.

• The resolutions established a UN sanctions committee and panel of experts to monitor and report on Iran’s compliance with the restrictions.

Q: What was the Obama administration’s position on snapback when it finalized the JCPOA in 2015?

• The Obama administration supported snapback if Iran failed to uphold the JCPOA. Senior administration officials frequently touted snapback’s unique design, which circumvents a Russian or Chinese veto in the Security Council.

• Former President Obama said in July 2015, “If Iran violates the deal, all of these sanctions will snap back into place.” He continued, “In the agreement, we’ve set it up so we can override Iran’s objection. And we don’t need Russia or China in order for us to get that override.” 

• Former President and then Vice President Joe Biden said in April 2015, “If at any point Iran breaks any of the commitments made in the agreement … we’ll have more time to respond, by snapping back sanctions or taking other steps to enforce compliance.”

• Former Secretary of State John Kerry said in July 2015, “If Iran fails in a material way to live up to these commitments, then the United States, the EU, and even the UN sanctions that initially brought Iran to the table can and will snap right back into place.”

Q: What is the timeline for imposing snapback?

By July 2025: Any party to the JCPOA (including the European Union) can trigger UNSCR 2231’s 35-day optional dispute resolution process to begin snapback:

• A Joint Commission of the JCPOA parties would have 15 days to try to resolve the issue.

• If the matter were not resolved, any party could refer it to the foreign ministers of the deal parties, who would have an additional 15 days to resolve it. The complaining party could also request that a three-member advisory board consider the matter and provide a non-binding opinion.

• The Joint Commission could consider the advisory board’s opinion for an additional five days.

• The E3 should avoid triggering the dispute resolution process, as it wastes time and offers Iran, Russia, and China an unnecessary platform to obfuscate and plead Tehran’s case.

• If Russia or China started the dispute resolution process, they could not run out the clock on snapback since there is no provision that prevents the E3 from moving to start snapback simultaneously.

By September 1, 2025: Any party to the JCPOA can trigger snapback — with or without using the dispute resolution mechanism.

• An E3 member can notify the UNSC president of Iran’s “significant non-performance” under the JCPOA.

• Within 10 days, if no participant state has submitted a resolution for a vote on whether to continue the lifting of UN Iran sanctions, the UNSC president must introduce such a resolution. The parties have 30 days to vote from the date of the original notification of “significant non-performance.”

• The resolution must pass for sanctions to remain lifted. This requirement effectively inverts the Security Council veto process. Instead of any one permanent Security Council member (the United States, Britain, France, Russia, or China) being able to use its veto to block a snapback, any one permanent member can guarantee a snapback, which would take place within 30 days of the original notification.  

• Whichever country holds the UNSC presidency can create procedural hurdles. Panama holds the presidency in August, South Korea in September, and Russia in October. Thus, the E3 should not wait to finalize the snapback until Russia’s presidency in October.

October 18, 2025: UNSCR 2231, its snapback mechanism, and all UN Iran sanctions resolutions expire if the West fails to act.

Q: What can the United States do to expedite the snapback process?

• Washington should continue coordinating with its European allies to ensure the E3 trigger snapback by August. During Trump’s first term, the E3 blocked U.S. efforts to initiate a snapback, viewing Washington as a party withdrawn from the JCPOA. The E3 can therefore provide international legitimacy to snapback.

• One reported option under consideration is for the E3 to submit a resolution extending the snapback and Resolution 2231 if Iran negotiates restrictions on its nuclear program. Such a move would entail Russia and China agreeing to a new resolution for a temporary extension.

• Under no circumstances should the United States and E3 let snapback lapse or extend the sunset provision, since the UN sanctions resolutions, in part, establish critical benchmarks for a new deal with Tehran that blocks all pathways to nuclear weapons and limits its malign missile, military, and other proliferation activities.

• Congress should fully support snapback, building on a February 2025 Senate resolution “calling on the United Kingdom, France, and Germany to initiate the snapback” and a companion resolution introduced by the House. It should also support full dismantlement of Iran’s nuclear fuel production, weaponization, and missile delivery capabilities, an effort backed by 51 Senate Republicans and 177 members of the House in May 2025 letters to President Trump.

Andrea Stricker is a research fellow and deputy director of the Nonproliferation and Biodefense Program at the Foundation for Defense of Democracies (FDD).