IAEA: Iran Maintains Stockpile for 10 Nuclear Warheads, Key Cache Likely Intact After Strikes
PARIS (Reuters) – Iran had accumulated enough highly enriched uranium to potentially fuel ten nuclear weapons before coordinated strikes targeted its atomic facilities last June, the head of the United Nations' nuclear watchdog stated Monday. A substantial portion of that stockpile, stored deep within a tunnel complex at Isfahan, is assessed to have survived the attacks unscathed.
International Atomic Energy Agency (IAEA) Director General Rafael Grossi, speaking to reporters in Paris, revealed that the agency estimates Iran possessed 440.9 kilograms of uranium enriched to up to 60% purity prior to the June strikes. This level is just a short technical step from the 90% considered weapons-grade.
"Based on our last inspection, we believe the Isfahan site held just over 200 kilograms of this 60% material," Grossi said. He noted the stock was "mainly" at Isfahan, with some quantities held elsewhere possibly destroyed. Satellite monitoring and other intelligence since the attacks have not shown signs of the material being moved from the tunnel complex, which was the only major target not severely damaged.
The disclosure confirms long-held suspicions by Western diplomats about Isfahan's role as a storage hub for Iran's most sensitive nuclear material. It also underscores the lingering tensions and unresolved questions following the unprecedented attacks, which Israel and the U.S. claimed were necessary to degrade Iran's advancing nuclear capabilities. Tehran has since barred IAEA inspectors from the bombed sites and ceased reporting on the status of its highly enriched uranium.
While Grossi reiterated that the IAEA has "no credible indication" of an active, coordinated nuclear weapons program in Iran, the sheer volume of material—and its continued existence—complicates non-proliferation efforts. The Natanz and Fordow enrichment plants were heavily damaged in June, but the survival of the Isfahan cache leaves a significant portion of Iran's nuclear leverage intact.
Analyst Perspectives:
"This is a stark reminder that military strikes, however precise, often treat symptoms, not the disease," says Marcus Thorne, a senior fellow at the Center for Non-Proliferation Studies. "The infrastructure and knowledge remain. The diplomatic track is still the only viable long-term solution."
"The IAEA's report is a damning indictment of Western inaction," argues Leila Karimi, a political commentator based in Tel Aviv. "It confirms our worst fears: the regime is sitting on a bomb's worth of material, shielded in tunnels, while the world debates. The strikes were justified, but clearly insufficient. The time for 'monitoring' is over."
"The key takeaway is the verification gap," notes David Chen, a former arms control negotiator. "Without access, the IAEA is operating in the dark. This uncertainty itself becomes a destabilizing factor, increasing the risk of miscalculation from all sides."
(Reporting by Francois Murphy; Edited by Sharon Singleton and Kevin Liffey)
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