By Micah Jonah
February 28, 2026
The International Atomic Energy Agency has urged Iran to grant immediate access to inspectors at its Isfahan nuclear facility, warning that most of the country’s highly enriched uranium is now believed to be stored at an underground tunnel complex there.
In a report circulated to member states on Friday, the United Nations nuclear watchdog said Iran continues to enrich uranium up to 60 percent purity, a level considered a short technical step from weapons grade material.
According to the agency, satellite imagery showed regular vehicular activity around the entrance to the tunnel complex at the Isfahan site, where uranium enriched up to 20 percent and 60 percent U 235 is believed to be stored.
The International Atomic Energy Agency said it could not verify the precise location of a fourth enrichment facility that Iran had previously announced it was setting up in Isfahan before last year’s 12 day conflict with Israel and the United States. Inspectors also said they were unaware of the operational status of the site or whether it currently contains nuclear material.
The development comes amid renewed diplomatic tensions between Tehran and Washington. The United States had previously claimed to have destroyed key Iranian nuclear facilities during the brief 12 day war, a claim that remains disputed.
There was no immediate official response from Tehran to the latest IAEA findings.
The report is expected to be discussed at the upcoming quarterly meeting of the agency’s 35 member Board of Governors in Vienna next week. The meeting will coincide with further indirect negotiations between the United States and Iran, mediated by Oman.
Iran is believed to possess more than 400 kilograms of uranium enriched to up to 60 percent purity, stockpiles that were last verified by IAEA inspectors in June before the outbreak of hostilities. Since then, Tehran has limited some cooperation with the agency and restricted access to sites struck during the conflict, accusing the watchdog of bias.
Iranian Foreign Minister, Abbas Araghchi recently said the United States must drop what he described as excessive demands in the ongoing talks. Washington has insisted that Iran dismantle its nuclear infrastructure, curb its ballistic missile programme and scale back support for regional allies.
As negotiations continue, the question of inspections and the fate of Iran’s enriched uranium stockpile remain central to efforts to ease tensions, prevent further escalation in the region.
