UN Nuclear Watchdog Cannot Verify Iran’s Underground Nuclear Plant. 441 Kg Uranium Stockpile In Question.

The United Nations nuclear watchdog has warned that it still does not know the exact location of an underground uranium enrichment plant in Iran or whether the facility contains nuclear material, raising fresh questions about Tehran's nuclear program as President Donald Trump insists Washington does not need a deal with the country.

In a confidential report circulated to member states Friday, the International Atomic Energy Agency (IAEA) said it was increasingly concerned about the Isfahan Fuel Enrichment Plant, which Iran declared in June 2025 but has never allowed international inspectors to examine.

"The Agency does not know IFEP's exact location, status for safeguards purposes or whether it contains nuclear material," the report said, according to Reuters.

The uncertainty extends to Iran's stockpile of highly enriched uranium. Before Israeli and American attacks on Iranian nuclear facilities in June 2025, the IAEA estimated that Tehran had accumulated 440.9 kilograms, or approximately 972 pounds, of uranium enriched to 60% purity.

That level is significantly higher than the enrichment generally required for civilian nuclear power plants and is a relatively short technical step from the 90% purity associated with weapons-grade uranium.

IAEA Director General Rafael Grossi previously warned that the material could potentially produce enough weapons-grade uranium for as many as 10 nuclear bombs if Iran decided to pursue weapons production. He stressed that the estimate did not mean Iran had manufactured nuclear weapons.

The agency has been unable to verify the stockpile's current quantity, composition or whereabouts since the June 2025 attacks. It has also been unable to establish whether the material remains at previously declared locations.

The Isfahan facility was declared to the IAEA on June 12, 2025, a day before Israel launched strikes against Iranian nuclear and military targets.

Inspectors had planned to visit the plant on June 13, but the inspection was canceled when the attacks began. The United States subsequently joined the military campaign, striking nuclear facilities during the 12-day conflict.

Diplomats believe the plant may be located within a tunnel complex at Isfahan, although the IAEA has been unable to confirm its precise location.

Grossi said in March that the agency believed a significant quantity of Iran's most highly enriched uranium could be stored in the tunnels.

The watchdog has also observed vehicle activity around the entrance to the tunnel complex in satellite imagery. It requested access in February 2026, but Iran did not permit inspectors to enter.

Friday's report said the agency remained concerned about its inability to examine the facility or review its design plans.

Iran has refused to resume inspections at nuclear facilities damaged during the attacks, arguing that continued American military threats make normal monitoring impossible.

According to a separate Associated Press report, Tehran told the IAEA this month that discussions about restoring inspections could not proceed while the United States continued threatening further strikes against its nuclear infrastructure.

Iran said it remained committed to its safeguards obligations but insisted that conditions must first be established for inspections to resume.

The IAEA rejected the continued absence of monitoring, saying the information gap presented a serious proliferation concern that required urgent action.

The agency has urged Tehran to take gradual technical measures to allow inspectors to return and said it was prepared to resume verification activities at short notice.

Since the June 2025 attacks, Bushehr has been the only Iranian nuclear facility inspected by the agency. Inspectors visited the nuclear power plant in September, but access to the damaged enrichment facilities remains restricted.

The latest warning comes as the Trump administration has sent conflicting signals over whether it intends to pursue another nuclear agreement with Tehran.

"We don't need a deal with Iran," Trump said Thursday, according to CBS News, after again claiming that the United States had achieved its military objectives in the conflict.

Iranian officials, meanwhile, have rejected proposals that would require the country to transfer its remaining enriched uranium abroad.

Earlier this week, Iranian security official Mohsen Rezaei said Tehran would not allow any of its enriched nuclear material to leave the country. Russia has previously offered to receive Iranian uranium as part of a possible arrangement, although Moscow has said the decision rests with Tehran.

Iran has long maintained that its nuclear program is intended for peaceful purposes. Western governments have questioned that position, while the IAEA has documented unresolved concerns about undeclared nuclear activities.

The agency's Board of Governors is scheduled to meet in Vienna from Nov. 18 to 20, with Iran's safeguards obligations among the matters expected to be discussed.