UNITED NATIONS — 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 U.S.-Israeli war, the head of the U.N. nuclear agency told The Associated Press.
Rafael Grossi said in an interview on Tuesday that the International Atomic Energy Agency has satellite images showing the effects of the latest U.S.-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 U.N. 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 the start of the June war. Those containers, believed to contain highly enriched uranium, likely remain there.
Grossi says 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 U.N. headquarters. Under its provisions, Iran is required to open its nuclear facilities to IAEA inspection, Grossi said.
Iran has 440.9 kilograms (972 pounds) 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 (about 440 pounds) 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 the AP last year, should Iran choose to rush for the bomb.
Tehran long has insisted its nuclear program is peaceful. President Donald Trump said one of the major reasons the United States went to war was to deny Iran the ability to develop nuclear weapons even as he has insisted that the strikes last June “obliterated” the country's atomic program.
IAEA has talked to Russia and others about taking Iran's highly enriched uranium
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 U.S. military operation in hostile territory.
“What's going to be important is that that material leaves Iran” or is blended to reduce its enrichment, he said.
Grossi said the IAEA participated in the last cycle of U.S.-Iran nuclear talks in February but hasn't been part of recent ceasefire negotiations mediated by Pakistan. He said the agency has been in discussions separately with the U.S. and informally with Iran.
The latest proposal from Iran would postpone discussions on its nuclear program but end its chokehold on the Strait of Hormuz, a crucial sea route for oil and natural gas shipments, if the U.S. lifts its blockade and ends the war.
Grossi described that as an indication that Iran wants to sequence how it confronts the objectives mandated by the U.S., including curbing its ballistic missile program and dealing with its proxies Hezbollah in Lebanon, Hamas in Gaza and the Houthis in Yemen.
“What is indispensable is that we address it,” the IAEA director-general said of Iran’s nuclear program.
A deal between the US and Iran will take ‘political will’
This will take “political will” from Tehran, he said, 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 U.S. 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.”
Secretary of State Marco Rubio told Fox News Channel this week that preventing Iran from attaining a nuclear weapon “remains the core issue” that must be confronted.
Asked if he thinks the Iranians are serious about making a deal, Rubio said 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.”
Grossi said in any political agreement, full IAEA inspections of Iran's nuclear facilities must take place.