Iran nuke inspectors detect uranium at 84% purity

International atomic monitors in Iran last week detected uranium enriched to levels just below that needed for a nuclear weapon, according to two senior diplomats, underscoring the risk that the country’s unrestrained atomic activities could prompt a new crisis.

The International Atomic Energy Agency is trying to clarify how Iran accumulated uranium enriched to 84% purity — the highest level found by inspectors in the country to date, and a concentration just 6% below what’s needed for a weapon. Iran had previously told the IAEA that its centrifuges were configured to enrich uranium to a 60% level of purity.

Inspectors need to determine whether Iran intentionally produced the material, or whether the concentration was an unintended accumulation within the network of pipes connecting the hundreds of fast-spinning centrifuges used to separate the isotopes. It’s the second time this month that monitors have detected suspicious enrichment-related activities.

A senior Iranian nuclear official denied Iran had enriched uranium beyond 60% purity “so far” and dismissed the development as “a smear and a distortion of the facts.”

“The existence of uranium particles above 60% does not mean the same thing as enrichment above 60%,” Behrouz Kamalvandi, spokesman for the Atomic Energy Organization of Iran told the state-run Islamic Republic News Agency.

The IAEA responded on Sunday and said it is discussing with Iran the results of the agency’s recent verification activities and will inform its board of directors as appropriate, according to a tweet citing IAEA Director General Rafael Mariano Grossi.

The development comes as Iran is increasingly isolated from the West and nuclear talks with world powers remain suspended. The country has also faced widespread condemnation for its deadly crackdown on major protests and the U.S. and European Union have tightened sanctions on Iran over its military support for Russia’s war on Ukraine.

Earlier on Sunday, Israel blamed Iran for a Feb. 10 attack on an oil tanker in the Arabian Sea. The incident came about a fortnight after a drone strike on a weapons depot near Iran’s city of Isfahan that Tehran blamed on Israel.

Even if the detected material was mistakenly accumulated because of technical difficulties in operating the centrifuge cascades — something that has happened before — it underscores the danger of Iran’s decision to produce highly enriched uranium, a diplomat said.

The IAEA has repeatedly said levels even at just 60% are technically indistinguishable from the level needed for a nuclear weapon. Most nuclear power reactors use material enriched to 5% purity.