The numbers tell the story, and they are not subtle. In 2015 the Iran nuclear deal capped uranium enrichment at 3.67 percent. By April 2021 Tehran told the UN’s nuclear watchdog it was enriching to 60 percent. Behind that jump are years of lost trust, and the families in the region who live with the consequences.
What the deal asked of Iran
Diplomats call the deal the JCPOA. Iran signed it with the P5+1, the five permanent Security Council members plus Germany. Talks wrapped up on July 14, 2015, and six days later the Council backed the text in Resolution 2231. Inspectors from the International Atomic Energy Agency were to verify that Iran kept its side.
The terms were concrete. Iran kept its stockpile under 300 kilograms of uranium enriched to 3.67 percent for 15 years, and enrichment was limited to Natanz. Operating centrifuges were cut to 5,060 IR-1 machines, with more than 13,000 excess machines dismantled and stored under IAEA monitoring. The aim, in the Council on Foreign Relations’ account, was to stretch the time Iran would need to build a bomb to at least a year. Before the deal, US intelligence officials had put that window at a few months.
Sanctions relief followed on January 16, 2016, once the IAEA certified Iran had taken the key steps.
Withdrawal and the staged response
On May 8, 2018, President Donald Trump announced the US was leaving the agreement and ordered the “highest level” of economic sanctions on Iran. Mr. Trump argued the deal failed to address Iran’s ballistic missiles or its proxy warfare. Iran accused Washington of reneging, and faulted Europe for giving way.
The response came in steps. In July 2019 Iran told the IAEA it had enriched uranium to “about 4.5 percent,” above the cap. In December 2020 its Guardian Council approved a law ordering enrichment raised to 20 percent, and on January 4, 2021 Iran began enriching to that level. In February Supreme Leader Ayatollah Ali Khamenei said enrichment would not stop at 20%. On April 13, 2021, Iran informed the IAEA it was moving to 60 percent at Natanz, using IR-6 centrifuges, and the agency soon verified it. Britain, France and Germany called it a serious development and said Iran had no believable civilian reason to enrich that high.
By March 2022 the IAEA put Iran’s enriched stockpile at about 3,197 kilograms, with 33 kilograms at 60 percent purity. In November 2022 Iran said it would enrich to 60 percent at Fordow too. The IAEA’s inspectors found uranium particles at Fordow measuring 83.7 percent purity, a finding that alarmed governments abroad. Iran pledged in March 2023 to cooperate more with the agency.
Talks that never closed
The countries began talks on bringing Washington and Tehran back in April 2021, with Vienna as the venue. They moved in fits and starts. President Joe Biden said the US would return if Iran complied. Over two years of on-and-off bargaining, the CFR wrote, left the sides nowhere near a compromise, and by late 2023 provisions of the deal had begun to expire. In April 2020, the US had declared its intent to snap back UN sanctions, and the other P5 members objected, saying a country that left the deal could not do it alone.
Sources
- The Joint Comprehensive Plan of Action (JCPOA) at a Glance (Arms Control Association)
- Timeline of Nuclear Diplomacy With Iran (Arms Control Association), excerpts
- What Is the Iran Nuclear Deal? (Council on Foreign Relations), excerpts
