UN nuclear watchdog renews concern over uninspected Iranian plant

The International Atomic Energy Agency (IAEA) has renewed its warning about an Iranian uranium enrichment plant it has never inspected, saying it does not know the facility’s exact location or whether it contains nuclear material.

In a confidential report circulated to member states on Friday and seen by Reuters and the Associated Press, the UN watchdog said it was “increasingly concerned” that Iran had not allowed inspectors to visit the Isfahan Fuel Enrichment Plant or examine its design information.

The uncertainty is longstanding. In February, the IAEA said it did not know the plant’s precise whereabouts, whether it was operating or whether it contained nuclear material. The absence of an inspection does not establish that material is there.

Iran notified the agency on 12 June 2025 that it intended to establish the plant. A planned check the following day was cancelled when Israeli attacks on Iran began. The US joined the strikes later that month. Iran told the IAEA in February 2026 that the plant had been subjected to attacks; the agency said it needed access to verify that account.

Separately, the IAEA has called for information and access to verify Iran’s enriched uranium stockpile. Its size and whereabouts remain uncertain. The agency estimated that Iran had 440.9kg of uranium enriched to up to 60% as of 13 June 2025, but the stockpile has not been verified since the attacks. The report does not establish that the stockpile is at the Isfahan enrichment plant.

According to AP, Iran told the agency this month that discussions on resuming inspections could not proceed while it faced threats of military attack. Tehran said it remained committed to fully implementing its safeguards obligations when conditions allowed. The IAEA encouraged Iran to consider gradual technical steps to permit inspectors to return.

Inspectors have continued some work in Iran: they visited the Bushehr nuclear power plant from 12 to 15 September. That was not an inspection of the Isfahan enrichment plant or verification of the uranium stockpile. Iran says its nuclear programme is peaceful and denies seeking nuclear weapons.