440.9 Kilograms of Iranian Uranium Without Current Verification Amid Lack of Access to Facilities
Key Facts
International Atomic Energy Agency Director General Rafael Grossi told the UN Security Council on 27 October that the agency had observed no repair or reconstruction activity since June 2025 at facilities damaged in military attacks during 2025 and 2026. The absence of observed reconstruction coincides with the continued inability to verify on the ground Iran’s declared nuclear facilities and related materials. The agency estimated that Iran held 440.9 kilograms of uranium enriched to up to 60% as of 13 June 2025, but it cannot determine the current stockpile’s size, composition or location. This gap puts verification of materials and facilities at the heart of Grossi’s briefing, while the agency’s observations on reconstruction do not establish the full current condition of the damaged sites. Grossi said the agency “has not identified any activity to repair or reconstruct any of the facilities damaged in the military attacks” during that period.
The agency’s estimate of the uranium stockpile dates to 13 June 2025 and was based on information Iran provided through 12 June, previous verification activities and estimates based on earlier operating records. The estimated total stockpile of enriched uranium then stood at 9,874.9 kilograms, including 440.9 kilograms enriched to up to 60%. That figure describes the stockpile on that date and is not a recent total the agency can confirm. In its report, the agency said it could not provide information on the “current size, composition or location” of Iran’s enriched uranium stockpile. It also cannot verify whether Iran has halted all enrichment activities, leaving questions about the stockpile and activity without direct verification.
The agency says the knowledge gap over uranium stocks declared at damaged facilities has persisted for more than a year, after it lost continuity of knowledge over those stocks. During the reporting period, it received no information from Iran on the status of its declared nuclear facilities for safeguards purposes or on related nuclear material. The agency was also unable to access any of those facilities on the ground during the period covered by the report. Iran did not engage on outstanding safeguards issues during the same period, according to the agency. The agency described the lack of information and inability to access facilities and materials as a proliferation and safeguards-compliance concern, and called for the matter to be addressed urgently.
At Isfahan, the agency observed regular vehicle activity near the entrance to the tunnel complex where uranium enriched to up to 20% and 60% had been stored, using satellite imagery. After the observation, the agency requested on-site verification, but Iran did not grant it access to the Isfahan Fuel Enrichment Plant. Iran informed the agency in February 2026 that the facility had also been subjected to military attacks. The agency has not identified the facility’s precise location and cannot verify whether it contains nuclear material. The Isfahan file thus combines observed vehicle movement with an access request that was not granted, while verification of the facility and related materials remains impossible.
Records from Bushehr show a different path from the access gap at enrichment facilities: the agency conducted an inspection and design verification at the nuclear power plant between 1 and 3 June 2026 as part of its routine quarterly verification activity. Iran also confirmed it would allow the agency to conduct two inspections at the plant’s Unit 1 in mid-September. The confirmation also covered design verification at all three units, BNPP-1, BNPP-2 and BNPP-3. The agency links these planned activities to the continuation of verification at the plant, while access to other declared nuclear facilities and related materials remains unavailable, according to the report. This contrast between arrangements at Bushehr and the inability to access other facilities stands out in the safeguards picture presented by the agency.
The agency’s report places the verification gap in the context of military attacks on the facilities, with verification activities halted when the attacks began. By the end of June 2025, the agency had decided to withdraw all its inspectors from Iran for safety reasons. In his briefing to the Security Council, Grossi linked sites damaged in attacks in 2025 and 2026 with the lack of observed repair or reconstruction work since June 2025. The absence of such work does not mean the agency verified the facilities’ full condition, as its report says it was unable to access the declared facilities during the reporting period. Grossi’s briefing and the September report’s information remain bounded by what the agency was able to observe and what it could not verify on the ground.