The International Atomic Energy Agency (IAEA) has not had access to some key nuclear facilities in Iran since Israel and the United States launched a 12-day conflict in June 2025 that saw strikes on nuclear sites.

Nuclear sites have also been struck in the war that erupted on February 28. The IAEA has repeatedly urged access.

"While the agency acknowledged that the military attacks on Iran's nuclear facilities and sites have created an unprecedented situation, it is critical for the agency to conduct verification activities in Iran without delay," the IAEA said in the report.

The report is to be discussed at an IAEA board of governors' meeting next week.

Prior to US strikes in June 2025, the IAEA calculated that Iran possessed approximately 440 kilogrammes of uranium enriched to 60 percent, which is close to the 90 percent needed to make a bomb and well above the 3.67-percent limit set by a 2015 now-defunct agreement with Iran.

Since June 2025, the fate of this stockpile has remained uncertain, with Tehran refusing access to IAEA inspectors at sites ravaged by US and Israeli strikes.

"The agency's lack of access to verify the previously declared highly enriched uranium and low enriched uranium for nearly a year -- which is long overdue according to standard safeguard practices -- is a matter of proliferation concern," it added.

"The director general (Rafael Grossi) calls on Iran to engage the agency constructively in order to facilitate the full and effective implementation of safeguards in Iran," it added.

Israel and the United States have long accused Iran of having ambitions to build a nuclear weapon, with President Donal Trump claiming that threat as justification for the conflict last year and the this year's war.

Trump has insisted that Iran must accept that it will not have a nuclear weapon and that the uranium is destroyed.

Tehran has repeatedly denied having any military amibitions, insisting on its right to the technology for civilian purposes.