JCPOA

What was the JCPOA?

On July 14, 2015, Iran reached an agreement with the European Union and six major powers – China, France, Russia, the United Kingdom, the US, and Germany – under which these states would roll back international economic sanctions and allow Iran greater participation in the global economy.

In return, Tehran committed to limiting activities that could be used to produce a nuclear weapon.

These included reducing its stockpile of enriched uranium by about 98 percent, to less than 300kg (660lb), and capping uranium enrichment at 3.67 percent – far below weapons-grade of 90 percent, but high enough for civilian purposes such as power generation.

Before the JCPOA, Iran operated roughly 20,000 uranium-enriching centrifuges. Under the deal, that number was cut to a maximum of 6,104, and only older-generation machines confined to two facilities, which were subject to international monitoring.

Centrifuges are machines which spin to increase the concentration of the uranium-235 isotope – enrichment – in uranium, a key step towards potential bomb-making

strictions on oil exports and banking were eased.

The deal came to halt when Trump formally withdrew Washington from the nuclear deal in 2018, a move widely criticised domestically and by foreign allies, and despite the IAEA saying Iran had complied with the agreement up to that point.

“The Iranian regime supports terrorism and exports violence, bloodshed and chaos across the Middle East. That is why we must put an end to Iran’s continued aggression and nuclear ambitions. They have not lived up to the spirit of their agreement,” he said in October 2017.

He reimposed crippling economic sanctions on Tehran as part of his “maximum pressure” tactic. These targeted Iran’s oil exports, as well as its shipping sector, banking system and other key industries.

The goal was to force Iran back to the negotiating table to agree to a new deal, which also included a discussion about Tehran’s missile capabilities, further curbs on enrichment and more scrutiny of its nuclear programme.

What has happened to Iran’s nuclear programme since the JCPOA?

During the JCPOA period, Iran’s nuclear programme was tightly constrained and heavily monitored. The IAEA repeatedly verified that Iran was complying with the deal’s terms, including one year after Trump announced the US’s withdrawal from the agreement.

Starting in mid-2019, however, Iran began incrementally breaching the deal’s limits, exceeding caps on uranium stockpiles and enrichment levels.

formed the nuclear watchdog that it planned to install more than 6,000 new centrifuges to enrich uranium.

In December 2024, the IAEA said Iran was rapidly enriching uranium to 60 percent purity, moving closer to the 90 percent threshold needed for weapons-grade material. Most recently, in 2025, the IAEA estimated that Iran had 440kg (970lb) of 60-percent enriched uranium.