IAEA Warns of Underground Nuclear Facility in Iran Amid Uranium Stockpile Concerns

A confidential International Atomic Energy Agency (IAEA) report obtained by Reuters on Saturday has raised concerns over an underground nuclear facility in Isfahan, Iran, where significant quantities of highly enriched uranium may be stored.

According to the report, Iran notified the nuclear watchdog in June 2025, shortly before Israel's Operation Rising Lion, that it was establishing the facility. However, Tehran has since denied inspectors access, leaving its precise location and operational status unverified.

Concerns Grow Over Iran's Uranium Stockpile

IAEA Director General Rafael Grossi believes a substantial portion of Iran's uranium enriched to 60% purity may be stored in underground tunnels at the Isfahan complex. Although below the approximately 90% enrichment typically associated with nuclear weapons, this level far exceeds the requirements of most civilian nuclear power applications.

The lack of access and technical information has raised serious proliferation concerns, as international inspectors cannot verify the whereabouts of the nuclear material or confirm that Iran's declared stockpile remains exclusively dedicated to peaceful purposes.

Iran Pressed to Allow Nuclear Inspections

The nuclear watchdog has demanded that Tehran urgently disclose the condition of its facilities and provide a complete accounting of its enriched uranium reserves. It is also seeking renewed access to previously bombed nuclear sites and the underground Isfahan complex to independently assess their status.

The findings highlight growing international concern over Iran's nuclear activities as critical gaps in monitoring leave the fate of substantial quantities of highly enriched uranium uncertain.