After surprise US bombing raids on Iranian uranium enrichment facilities over the weekend, the head of the UN-backed nuclear watchdog on Monday appealed for immediate access to the targeted sites to assess the damage that is likely "very significant".
Rafael Grossi, head of the International Atomic Energy Agency ( IAEA ), was addressing the agency's Board of Governors, amid fresh reports of new Israeli missile strikes on Iranian military sites in Tehran and elsewhere earlier on Monday. Iranian weapons fire has also been reported across Israel.
Mr. Grossi - who also addressed an emergency meeting of the UN Security Council on Sunday - insisted that the agency's weapons inspectors should return to Iran's nuclear sites and account for their stockpiles.
There is particular concern about 400 kilogrammes of uranium enriched to 60 per cent by Iran.
Under the terms of a 2015 nuclear deal with the international community, Iran is permitted to enrich the naturally occurring radioactive material to less than four per cent.
"Craters are now visible at the Fordow site, Iran's main location for enriching uranium at 60 per cent, indicating the use of ground-penetrating munitions; this is consistent with statements from the United States," he told the IAEA Board of Governors. "At this time, no one including the IAEA, is in a position to have fully assessed the underground damage at Fordow."
Mr. Grossi said that taking into account the highly explosive payload used in the US attacks, "very significant damage is expected to have occurred" to the highly sensitive centrifuge machinery used to enrich uranium at Fordow.
Several sites hit
Fordow is one of several nuclear-related sites across Iran that are known to have been damaged in the strikes by the United States, including those in Esfahan, Arak and Tehran.
In comments to the UN Security Council in New York on Sunday, the IAEA chief said that although radiation levels remained normal outside these nuclear facilities, deep concerns remained about Iran's operational nuclear plant at Bushehr.
Any strike on Bushehr could trigger a massive radiation release across the region - "the risk is real", Mr. Grossi said.
Eleven days after Israel launched air and missile strikes at Iranian military and nuclear sites, some 430 people are believed to have been killed in Iran, most of them civilians.
According to Israeli reports, 25 people have been killed and more than 1,300 injured by Iranian missile strikes.
