The Joint Comprehensive Plan of Action (JCPOA) is a multilateral agreement finalized on July 14, 2015, between Iran and the P5+1 group—China, France, Germany, Russia, the United Kingdom, and the United States—plus the European Union. Its origin lies in the international community's concern over Iran's nuclear program, which was suspected of aiming to develop nuclear weapons, leading to years of negotiations and multiple United Nations Security Council (UNSC) sanctions. The JCPOA was created to solve the problem of potential nuclear proliferation by ensuring Iran's nuclear program would be exclusively peaceful in exchange for the lifting of nuclear-related international sanctions.
The mechanism of the JCPOA involves Iran accepting significant, time-bound restrictions on its nuclear activities, verified by the International Atomic Energy Agency (IAEA). Key provisions include capping uranium enrichment at 3.67% for 15 years and reducing its stockpile of enriched uranium to 300 kg. Iran also agreed to reduce its operating centrifuges to 5,060 IR-1 machines for 10 years and to redesign the Arak heavy-water reactor to prevent the production of weapons-grade plutonium. In return, the P5+1 and EU agreed to lift nuclear-related sanctions, which took effect on Implementation Day, January 16, 2016, after the IAEA verified Iran's initial steps. The agreement is connected to the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), as Iran is a signatory, and was endorsed by UNSC Resolution 2231.
The JCPOA has changed significantly since its creation: the United States unilaterally withdrew from the agreement in 2018 and reimposed sanctions. Following the US withdrawal, Iran began to renege on its commitments in 2019, including increasing its uranium enrichment purity and stockpile beyond the limits set in the JCPOA. The core structure of the agreement remains the same—sanctions relief for nuclear restrictions—but the mutual commitments are currently not being fully implemented by all parties.