Recent airstrikes by the United States and Israel targeting key nuclear facilities in Iran have left international inspectors grappling with a critical dilemma: determining the fate of Tehran’s enriched uranium reserves, including material nearing weapons-grade level.
The strikes, carried out last weekend, hit three prominent nuclear sites—Fordow, Natanz, and Isfahan. Former U.S. President Donald Trump later claimed the operations had “wiped out” these installations, using specialized bunker-penetrating weaponry.
However, the International Atomic Energy Agency (IAEA), which oversees nuclear activities in Iran, remains uncertain about the extent of the actual damage at Fordow—a deeply fortified facility hidden within mountainous terrain and previously responsible for producing Iran’s highest-grade enriched uranium.
IAEA Director General Rafael Grossi indicated on Monday that while the centrifuges at Fordow likely sustained serious damage, the status of Iran’s enriched uranium remains unclear. Of particular concern is the fate of approximately nine metric tons of enriched uranium—over 400 kilograms of which had reached nearly 60% purity, dangerously close to the 90% level required for nuclear weapons.
Western intelligence agencies are now racing to track the stockpile, amid growing fears that the airstrikes may have inadvertently given Iran an opportunity to secretly relocate some or all of its nuclear material.
Speaking to Reuters, more than a dozen current and former nuclear non-proliferation officials acknowledged the difficulty the IAEA will face in conducting an effective investigation. They warned that any assessment of the site could take months or even years, given the complex task of recovering evidence from bombed-out buildings, conducting forensic analysis, and performing environmental sampling.
Olli Heinonen, the IAEA’s former chief inspector from 2005 to 2010, now with the Stimson Center think tank in Washington, emphasized that locating residual nuclear material will not be easy. “Some of it could be buried deep under rubble or have been dispersed during the strikes,” he explained.
According to IAEA estimates, the amount of uranium Iran had enriched up to 60% could, if further processed, yield enough fissile material for roughly nine nuclear weapons. Even partial loss of accounting for this stockpile would spark alarm among Western nations, many of whom suspect Iran is keeping open its option to develop nuclear arms.
There are already signs suggesting Tehran may have preemptively shifted some of its nuclear stock before the attacks took place. Grossi revealed that on June 13, the day of the initial Israeli strikes, Iranian officials notified the agency of protective measures being taken to safeguard nuclear equipment and materials. Although Iran did not specify what those steps entailed, Grossi suggested this may imply the uranium was relocated.
A Western diplomat familiar with the situation, speaking anonymously due to the sensitivity of the matter, noted that satellite images captured days before the strikes showed significant vehicle movement near Fordow, including truck convoys. This observation has fueled speculation that Iran anticipated the attack and acted swiftly to move its stockpile.
Nevertheless, U.S. Defense Secretary Pete Hegseth stated on Thursday that Washington possesses no solid intelligence confirming such a transfer of uranium.
Former President Trump has also rejected reports that Iran managed to shift material. In a Fox News interview set to air Sunday, he insisted the Iranians lacked the time and capability to move heavy nuclear stockpiles unnoticed. “It’s not something you just pick up and carry. It’s a massive, heavy load,” Trump remarked. “They had no idea the strikes were coming.”
The White House declined to comment when approached by Reuters, while the State Department directed inquiries back to Trump’s public statements.
Another Western diplomat, referencing Iran’s history of disputes with the IAEA over unexplained uranium traces found at undeclared sites, predicted that verifying the current location and status of Iran’s enriched uranium would be a long and difficult process.
“This is shaping up to be another prolonged game of cat and mouse,” the diplomat said.
For its part, Tehran maintains that it remains in full compliance with its international nuclear obligations.
