Iran began enriching uranium Friday to its highest level ever, edging closer to weapons-grade levels to pressure talks in Vienna aimed at restoring its nuclear deal with world powers after an attack on its main atomic site.
A top official said only a few grams an hour of uranium gas would be enriched up to 60 percent purity — triple the level it once did but at a rate far slower than what Tehran could produce. International inspectors already said Iran planned to do so above-ground at its Natanz nuclear site, not deep within its underground halls hardened to withstand airstrikes.
The move is likely to raise tensions even as Iran negotiates in Vienna over a way to allow the U.S. back into the agreement and lift the crushing economic sanctions it faces. However, its scope also provides Iran with a way to quickly de-escalate if it chose.
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The announcement also marks a significant escalation after the attack that damaged centrifuges at Natanz, an attack this past weekend suspected of having been carried out by Israel. While Israel has yet to claim it, it comes amid a long-running shadow war between the two Mideast rivals.
Mohammad Bagher Qalibaf, Iran's parliament speaker, announced the move in a Twitter post later acknowledged by Iranian state television.
"The young and God-believing Iranian scientists managed to achieve a 60 percent enriched uranium product," Qalibaf said. "I congratulate the brave nation of Islamic Iran on this success. The Iranian nation's willpower is miraculous and can defuse any conspiracy."
The head of the Atomic Energy Organization of Iran, the country's civilian nuclear arm, later acknowledged the move to 60 percent, according to state TV. Ali Akbar Salehi said the centrifuges now produce 9 grams an hour, but that would drop to 5 grams an hour in the coming days.
"Any enrichment level that we desire is in our reach at the moment and we can do it at any time we want," Salehi said.
While 60 percent is higher than any level Iran previously enriched uranium, it is still lower than weapons-grade levels of 90 percent.
Iran had been enriching up to 20 percent — even that was a short technical step to weapons grade. The deal limited Iran's enrichment to 3.67 percent.
The International Atomic Energy Agency, which monitors Iran's nuclear program, did not immediately respond to a request for comment. Earlier this week, it sent its inspectors to Natanz and confirmed Iran was preparing to begin 60 percent enrichment at an above-ground facility at the site.
Iran insists its nuclear program is peaceful, though the West and the IAEA say Tehran had an organized military nuclear program up until the end of 2003. An annual U.S. intelligence report released Tuesday maintained the American assessment that "Iran is not currently undertaking the key nuclear weapons-development activities that we judge would be necessary to produce a nuclear device."
Iran previously had said it could use uranium enriched up to 60 percent for nuclear-powered ships. However, the Islamic Republic currently has no such ships in its navy.
The 2015 nuclear deal, which former President Donald Trump unilaterally withdrew the U.S. from in 2018, prevented Iran from stockpiling enough high-enriched uranium to be able to pursue a nuclear weapon if it chose in exchange for the lifting of economic sanctions.