The International Atomic Energy Agency (IAEA) has not seen any activity at key nuclear sites, judging from satellite images, since the start of the Middle East war, a diplomatic source said.

But the IAEA has not had access to some key nuclear facilities in Iran since Israel, joined by the United States, launched a 12-day conflict in June 2025 that included strikes on nuclear sites.

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

According to a CNN report on Sunday, satellite images show that Iran has unblocked 50 out of the 69 tunnel entrances bombed by the US and Israel at 18 underground missile facilities.

A diplomatic source said the IAEA had detected "no more movement" at key sites, such as Isfahan and Natanz, since the start of the war.

In its report, the IAEA said it conducted an inspection this week at the Bushehr nuclear power plant, but not other sites.

The Bushehr plant was built and operated with Russian assistance for civilian purposes but was targeted in the war.

- 'Without delay' -

"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.

"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.

IAEA head 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, evoking the "utmost urgency".

Israel and the United States have long accused Iran of wanting to build a nuclear weapon, with President Donald Trump claiming that threat as justification for attacking Iran.

Trump has insisted that Iran must accept in any deal to end the war that it will not have a nuclear weapon and that the uranium is destroyed.

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