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"We notice there's a little activity at Pickaxe. I would advise Iran not to get cute because we will have to hit them very hard," Trump said Wednesday at the midterm Republican convention.
Situated near Iran's heavily damaged Natanz uranium enrichment facility, Pickaxe Mountain is , showed more road activity at Pickaxe Mountain in 2026"than at any point in the site's history" and "a clear surge" in construction activity.
The latest data indicates that activity at the site "has shifted from active excavation toward probable internal construction and continued exterior reinforcement," CSIS said.
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Iran has repeatedly denied it is seeking nuclear weapons.
A spokesperson at Iran's Embassy in London was not immediately available to respond to a CNBC request for comment.
U.S. forces three Iranian nuclear sites in June 2025, including Natanz, Fordow and Isfahan, which American officials said at the time had significantly set back the prospect of Tehran building a nuclear weapon.
Trump: Iran war won't end until after midterm elections
Earlier in the week, U.S. Central Command forces 
Speaking to reporters on Wednesday, Trump said he did not think the U.S.-Iran war would end until after November's midterm elections. "I think the war will end immediately after the election because they can't hold out any longer," Trump said.
The U.S. president later added that some short-term economic pain for American consumers was worth it to prevent Iran from developing nuclear weapons.
