The United Nations nuclear watchdog has said it does not know where one of Iran’s declared uranium enrichment plants is, whether it is operating, or whether it contains nuclear material, in its starkest warning yet about how little it can now see inside Tehran’s nuclear programme.
In a confidential quarterly report circulated to member states on Friday, the International Atomic Energy Agency (IAEA) said it was “increasingly concerned” about the Isfahan Fuel Enrichment Plant, known as IFEP. Iran declared the underground facility to the agency on 12 June 2025, but inspectors have never been allowed inside.
“The Agency does not know IFEP’s exact location, status for safeguards purposes or whether it contains nuclear material,” the report said, adding that Iran had also refused to let the agency inspect the plant or see its design plans. An inspection had been scheduled for 13 June 2025, the day Israel and the United States began a 12-day bombing campaign against Iran’s nuclear sites.
Iran has not allowed IAEA inspectors back into any of the facilities hit in that campaign, which destroyed or badly damaged its other enrichment plants. The only site inspectors have visited since June 2025 is the Bushehr nuclear power reactor, in September this year.
Tehran told the agency this month that talks on resuming monitoring could not proceed while it faced what it called “persistent, explicit, and public threats” from the President of the United States to attack it again, particularly its nuclear facilities.
The report also said the agency had lost track of Iran’s stockpile of highly enriched uranium. The last verified figure, from 13 June 2025, put it at 440.9 kilograms enriched to 60 per cent purity, a short technical step from the 90 per cent needed for weapons. The agency’s director general, Rafael Grossi, has previously warned that the stockpile could allow Iran to build as many as 10 nuclear bombs should it decide to weaponise its programme.
Grossi said in March that the agency believed a significant amount of Iran’s most highly enriched uranium was held in a tunnel complex at Isfahan. The report said the agency was now unable to conclude that no declared nuclear material had been diverted, calling the gap in its knowledge “a matter of serious proliferation concern” that “needs to be rectified with the utmost urgency”. Grossi urged Tehran to take gradual, technical steps to let inspectors return.
Sources: Reuters, “IAEA increasingly concerned about Iranian enrichment plant, its report says” (https://www.reuters.com/world/china/iaea-increasingly-concerned-about-iranian-enrichment-plant-its-report-says-2026-11-13/); Associated Press, “Iran Tells UN Nuclear Agency That Monitoring Cannot Proceed While It Is Under Threat” (https://www.military.com/iran-tells-un-nuclear-agency-that-monitoring-cannot-proceed-while-it-is-under-threat).
