ERBIL, Kurdistan Region - The International Atomic Energy Agency (IAEA) has warned that it is “increasingly concerned” about an Iranian uranium-enrichment plant in Isfahan that it has never inspected, Reuters reported Friday, citing a confidential report.
The quarterly report to member states, seen by Reuters, also warned that Iran has continued to deny inspectors access to nuclear facilities bombed by Israel and the United States in June 2025, preventing the agency from verifying the status of Tehran’s enriched uranium stockpile.
The Isfahan Fuel Enrichment Plant (IFEP) was declared by Tehran on June 12, 2025, a day before the IAEA was scheduled to inspect it. However, the outbreak of a 12-day bombing campaign by Israel and the United States prevented the inspection from taking place.
“The Agency does not know IFEP’s exact location, status for safeguards purposes or whether it contains nuclear material,” the report stated.
The agency also expressed concern that Tehran had not allowed inspectors to visit the facility or examine its design plans.
The warning marks the latest development in ongoing tensions between Tehran and Washington, with the latter repeatedly insisting that Iran must not be allowed to acquire nuclear weapons.
IAEA chief Rafael Grossi said in March that the agency believed a significant amount of Iran’s most highly enriched uranium was stored in a tunnel complex in Isfahan, where diplomats suspect the IFEP is located.
The agency has previously warned that Iran’s uranium enrichment had reached 60 percent purity, a short technical step from the 90 percent generally considered weapons-grade.
According to the IAEA’s last verified estimate in June 2025, Iran possessed approximately 440.9 kilograms of uranium enriched to 60 percent purity. However, the agency has since been unable to verify the current size, composition or whereabouts of the stockpile.
The IAEA has urged Tehran to disclose the status of its enrichment facilities, account for its highly enriched uranium and allow inspectors to return to sites damaged during the bombing campaign.
Iran has maintained that its nuclear program is intended for peaceful purposes and has argued that military attacks and continuing security threats have complicated the resumption of inspections.
US President Donald Trump has repeatedly insisted that Iran must not be allowed to develop nuclear weapons, making the issue a central focus of Washington’s policy toward Tehran.
The US State Department recently offered up to $20 million and the possibility of relocation to individuals providing information about Tehran’s nuclear program through its Rewards for Justice initiative.
Diplomatic efforts to resolve tensions between Washington and Tehran continue, although the two sides remain divided over Iran’s nuclear program and the terms of a potential agreement.


