The US-Iran nuclear deal, formally known as the Joint Comprehensive Plan of Action (JCPOA), is a multilateral agreement reached in July 2015 between Iran and the P5+1 countries (the United States, United Kingdom, France, Russia, China, and Germany), plus the European Union. The deal aimed to limit Iran's nuclear program in exchange for relief from economic sanctions. Under the JCPOA, Iran agreed to restrict its uranium enrichment to 3.67% purity, reduce its enriched uranium stockpile to 300 kilograms, and allow inspections by the International Atomic Energy Agency (IAEA). In return, sanctions on Iran's oil exports, banking, and other sectors were lifted. The agreement was seen as a major diplomatic achievement, but it faced opposition from Israel, Saudi Arabia, and many US Republicans who argued it did not address Iran's ballistic missile program or support for proxy groups. In May 2018, President Donald Trump unilaterally withdrew the United States from the JCPOA, calling it a 'horrible one-sided deal' and reimposed sanctions on Iran. Iran responded by gradually exceeding the deal's limits on enrichment, stockpile size, and centrifuge development. By 2020, Iran was enriching uranium to 60% purity, close to weapons-grade levels of 90%. The Biden administration, which took office in January 2021, expressed interest in rejoining the deal but negotiations in Vienna from April 2021 to August 2022 failed to restore the JCPOA. Key sticking points included the scope of sanctions relief, Iran's demand for guarantees that future US presidents would not withdraw again, and Iran's enrichment activities. As of 2025, the JCPOA is effectively defunct. Iran has enriched uranium to up to 60% purity and has an estimated stockpile of over 5,000 kilograms of enriched uranium, far exceeding the 300-kilogram limit. The IAEA has reported that Iran is the only non-nuclear-weapon state enriching uranium to 60% and that it has not provided credible answers about undeclared nuclear materials found at several sites. The US has maintained maximum pressure sanctions, while Iran has expanded its nuclear program and deepened ties with Russia and China. The possibility of a new deal in 2026 depends on political will in both countries, the outcome of US elections, and Iran's strategic calculus amid regional tensions. Interest in the topic remains high because a new deal could prevent Iran from developing a nuclear weapon, which would have major consequences for Middle East security, global oil markets, and nonproliferation efforts. Conversely, failure to reach a deal could lead to a nuclear-armed Iran, prompting a regional arms race and potential military conflict. The prediction market asks whether the US and Iran will agree to a new formal written agreement by 2026 that imposes verifiable restrictions on Iran's nuclear program, including limits on uranium enrichment.

Historical Context

The US-Iran nuclear dispute dates back to the 1950s, when the US provided Iran with its first nuclear reactor under the Atoms for Peace program. Iran's nuclear program expanded under the Shah, but after the 1979 Islamic Revolution, the US cut ties and Iran's nuclear activities became more secretive. In the 1990s, the US accused Iran of pursuing nuclear weapons, leading to sanctions. By 2002, an Iranian opposition group revealed undeclared nuclear facilities at Natanz and Arak, prompting IAEA investigations. Negotiations between Iran and the EU3 (UK, France, Germany) began in 2003 but stalled. In 2006, the UN Security Council imposed sanctions on Iran. The election of Hassan Rouhani in 2013, a moderate, opened the door for talks. The JCPOA was signed on July 14, 2015, after 20 months of negotiations. It was endorsed by UN Security Council Resolution 2231. The deal was implemented in January 2016, with Iran shipping out 98% of its enriched uranium and dismantling centrifuges. The deal unraveled after Trump's withdrawal in 2018. Iran began violating the deal in 2019, enriching to 4.5% and later 60%. By 2021, Iran's breakout time (the time needed to produce enough fissile material for one bomb) had shrunk from 12 months to a few weeks. The Biden administration's attempts to restore the deal failed, and by 2024, the JCPOA was considered dead. The IAEA board of governors passed resolutions criticizing Iran for non-cooperation, and Iran responded by expanding its nuclear program and barring some IAEA inspectors.