The majority of Iran’s highly enriched uranium is likely still at its Isfahan nuclear complex, which was bombarded by airstrikes last year and faced less intense attacks in this year’s US-Israeli war, the UN nuclear agency’s leader.
Rafael Grossi told The Associated Press on Tuesday that the International Atomic Energy Agency has satellite images showing the effects of the latest US-Israeli airstrikes against Iran and that “we continue to get information.”
IAEA inspections ended at Isfahan when Israel last June launched a 12-day war that saw the United States bomb three Iranian nuclear sites.
The UN nuclear watchdog believes a large percentage of Iran’s highly enriched uranium “was stored there in June 2025 when the 12-day war broke out, and it has been there ever since,” Grossi said.
“We haven’t been able to inspect or to reject that the material is there and that the seals — the IAEA seals — remain there,” he said. “I hope we’ll be able to do that, so what I tell you is our best estimate.”
Images from an Airbus satellite show a truck loaded with 18 blue containers going into a tunnel at the Isfahan Nuclear Technology Center on June 9, 2025, just before last year’s war started. Those containers, believed to contain highly enriched uranium, likely remain there.
All Iran’s nuclear sites must be inspected
The IAEA also wants to inspect Iran’s nuclear facilities at Natanz and Fordo, where there is also some nuclear material, the IAEA director general added.
Iran is a party to the Nuclear Nonproliferation Treaty, whose five-year review is underway at UN headquarters. Under its provisions, Iran is required to open its nuclear facilities to IAEA inspection, Grossi said.
Iran has 440.9 kilograms of uranium that is enriched up to 60% purity, a short, technical step from weapons-grade levels of 90%, according to the agency. Grossi has said the IAEA believes roughly 200 kilograms is stored in tunnels at the Isfahan site.
The Iranian stockpile could allow the country to build as many as 10 nuclear bombs, should it decide to weaponize its program, Grossi told AP last year.
Tehran long has insisted its nuclear program is peaceful. US President Donald Trump said one of the major reasons the US went to war was to deny Iran the ability to develop nuclear weapons, even as he has insisted that the strikes last summer “obliterated” the country’s atomic program.
Last Saturday, The New York Times reported that Iran has a total of 11 tons of uranium, at various enrichment levels. A nuclear expert told the newspaper that Iran’s stockpile could yield roughly 35 to 55 weapons depending on its skill in making not only the bomb’s fuel core but such nonnuclear parts as detonators that spark the chain reactions. Another expert said Iran’s stockpile was sufficient for 50 to 100 bombs if further enriched.
Taking the highly enriched uranium out of Iran
Grossi said the IAEA has discussed with Russia and others the possibility of sending Iran’s highly enriched uranium out of the country — a complex operation that would require either a political agreement or a major US military operation in hostile territory.
Grossi noted that “what’s going to be important is that that material leaves Iran” or is blended to reduce its enrichment.
He said the IAEA participated in US-Iran nuclear talks in February but has not been part of recent ceasefire negotiations mediated by Pakistan. He said the agency has been in discussions separately with the US and informally with Iran.
The IAEA chief said negotiations now are a “completely different ballgame” because of Iran’s “exponential progress” not only on enriching uranium but using the latest generation of centrifuges, different compounds and new facilities.
‘Political will’
It would take “political will” from Tehran to reach a deal, Grossi told AP, stressing that “Iran has to be convinced that it is important to negotiate.”
Iran’s leaders say they are willing to negotiate and so does the Republican US president, Grossi said, but “where the frustration kicks in, apparently for both, is that they do not seem to come to agreement, or be at an eye-to-eye level, on what needs to be done first, or on how.”
Calling himself a negotiator who likes to see a “flicker of hope,” Grossi noted that “one important thing is that there is apparently an interest on both sides to come to an agreement.”
Asked if he thinks the Iranians are serious about making a deal, Secretary of State Marco Rubio told Fox News Channel this week that they are skilled negotiators looking to buy time and that any agreement must be “one that definitively prevents them from sprinting towards a nuclear weapon at any point.”
