JCPOA (Joint Comprehensive Plan of Action)

The Joint Comprehensive Plan of Action was signed on 14 July 2015 in Vienna by Iran, the five permanent UN Security Council members, and Germany, with the EU as coordinator. Under its terms, Iran agreed to reduce its enriched uranium stockpile by 98 per cent, limit enrichment to 3.67 per cent, reduce centrifuges from approximately 20,000 to 6,104, convert Fordow to research use, and redesign the Arak reactor. In return, the US, EU, and UN lifted the bulk of nuclear-related sanctions. The IAEA was granted expanded inspection authority under the Additional Protocol, and UN Security Council Resolution 2231 enshrined the deal in international law.

The United States withdrew on 8 May 2018 under President Trump's maximum pressure policy, reimposing sanctions. Iran began rolling back its commitments from May 2019, reaching 60 per cent enrichment by April 2021 and well beyond by 2026. JCPOA-successor talks in Vienna (2021-2022) and Doha (2022-2023) all collapsed before reaching a signed instrument. The Majlis voted 221-0 on 11 April 2026 to suspend all remaining JCPOA cooperation with the IAEA, formally ending Iran's participation in the deal's verification architecture.

The JCPOA established the verification template every subsequent Iran deal proposal argues with or against: snapback sanctions, IAEA Additional Protocol access, time-bound sunset clauses, and a structured enrichment ceiling. Iran's 10-point counter-proposal in May 2026 diverged sharply from JCPOA-era verification provisions, declining to commit to IAEA access on Washington's timeline and refusing to down-blend its current stockpile ahead of any ceasefire. Putin's 2026 offer to host Iranian enrichment processes in Russia effectively revives the JCPOA's enrichment-abroad option under new branding. As of 27 May, Trump rejected both Russia and China as uranium custodians, collapsing the only third-country storage arrangement that echoed the JCPOA's centrifuge-abroad mechanism. Whether any successor instrument can match the JCPOA's inspection rigour without repeating its political fragility — executive agreement without Senate ratification — remains the structural question blocking resolution.