IAEA report: Iran is hiding the fate of its enriched uranium stockpile - and blocking access to nuclear facilities

Iran continues to prevent International Atomic Energy Agency (IAEA) inspectors from accessing its central nuclear facilities, thereby failing to allow the agency to determine the location of its enriched uranium stockpile, its status, and whether Tehran is continuing enrichment activities, The New York Times reported today (Tuesday), based on an 11-page internal IAEA report.

The report, dated September 1, was transferred to member states of the agency ahead of the Board of Governors meeting to be held next week in Vienna. During the meeting, countries are expected to discuss the promotion of a new resolution to condemn Iran for its lack of cooperation with international inspection mechanisms.

According to the report, IAEA inspectors have not received access to the central enrichment facilities in Fordo, Natanz, and Isfahan since June 2025. Because of this, the agency cannot verify the status, composition, and location of Iran's enriched uranium stockpile, including hundreds of kilograms enriched to a level of 60%, close to the level required for producing nuclear weapons.

The latest information in the agency's possession is based on data provided by Iran until June 12, 2025. According to those data, Iran held a total of about 9,874.9 kilograms of enriched uranium at various levels, of which 184.1 kilograms were enriched to 20%, and 440.9 kilograms were enriched to 60%.

Since then, the agency has not managed to continuously track the material. The report stated that due to the denial of access, "the agency cannot provide any information on the current size of the enriched uranium stockpile in Iran, its composition, or its whereabouts, nor determine if Iran has ceased all enrichment activities."

The IAEA also cannot determine how many centrifuges are currently in Iran's possession, where they are placed, and whether Tehran continues to produce and test new centrifuges. This is a significant information gap, because centrifuges are the systems used for uranium enrichment, and their operation rate and composition directly affect the time required to reach a military enrichment level.

In the report, special concern was also expressed regarding a fourth enrichment facility in the Isfahan area, the establishment of which Iran announced in June 2025. Tehran never allowed IAEA inspectors to enter the facility, and the agency does not know for sure even where it is located, and cannot determine if nuclear materials are held there or if enrichment activity is taking place.

IAEA Director General Rafael Grossi warned in the report about the significance of the loss of oversight over the Iranian nuclear program. "The lack of information in the agency's possession on this material, and the lack of access to the facilities for the purpose of verifying it, are a matter that raises concern in terms of nuclear weapons proliferation," he wrote.

Grossi called on Iran to allow inspectors to return to the facilities with the utmost urgency. According to him, without physical access to the sites and without updated information from Tehran, the agency is unable to ensure that the declared nuclear material is not being diverted to other uses.

Iran consistently denies that it is seeking to produce nuclear weapons and claims that its program is intended for civilian purposes only. However, according to The New York Times, it has never provided the IAEA with a satisfactory explanation for the need to enrich uranium to a level of 60%.

Oversight of nuclear facilities effectively ceased in June 2025, after Israel and the USA attacked in Iran for 12 days, among other things at the known nuclear facilities in Fordo, Natanz, and Isfahan. According to estimates, some of the enriched uranium stockpiles were buried or trapped at the damaged sites, but in the absence of access, it is impossible to determine if the material is still there, if it was moved beforehand, or if it can be extracted.

After the attacks, Iran suspended cooperation with the IAEA. Later, it announced that it would allow inspectors to return to the country, but in practice, they were not given access to the damaged enrichment sites. Tehran claimed that entry to the attacked facilities requires the formulation of safety procedures and special protocols for inspecting nuclear sites damaged in military action.

According to the new report, Iran committed to allow IAEA inspectors to arrive later this month at the civilian nuclear facilities in Bushehr. However, such a visit will not solve the focus of the dispute: the lack of access to Fordo, Natanz, the Isfahan facilities, and the enriched uranium stockpile, whose fate has been unknown to the agency for more than a year.