President Donald Trump has stated he does not care about Iran's stock of highly enriched uranium (HEU), arguing it is deep underground and can be monitored by satellite, raising questions about a key US justification for the war. Experts warn that if the US-Israeli offensive ends with Tehran still controlling its 440kg HEU stockpile, Iran would be significantly closer to developing nuclear warheads than if the US had pursued a negotiated settlement that was on the table before the conflict began on 28 February.
In an interview with Reuters on Wednesday, Trump said of the stockpile: 'That's so far underground, I don't care about that.' Later, in a White House address, he added: 'If we see them make a move, even a move for it, we will hit them with missiles very hard again.' These remarks appear to rule out a risky military mission to retrieve the HEU, which is believed to be hidden in deep underground shafts and is enough for about a dozen warheads.
The apparent decision to leave the HEU in Iranian hands conflicts with Trump's earlier assertions that a principal war aim was to ensure Iran could never make a nuclear bomb. He has repeatedly claimed Iran was two to four weeks from producing a nuclear weapon, a claim rejected by most experts. Nuclear proliferation experts say that if the HEU remains under Iranian control, Tehran would be closer to nuclear capability than under the proposed settlement being negotiated in Geneva on 26 February, two days before the war began.
In those US-Iran talks, Iranian officials proposed diluting the HEU to low-enriched uranium and agreed to keep only a smaller stockpile on its territory. The proposal also included a multiyear pause in enrichment and a restoration of comprehensive IAEA monitoring. Omani mediators and UK national security adviser Jonathan Powell believed significant progress had been made. A further round of talks was scheduled for Vienna but was cancelled due to the US-Israeli attack.
Emma Belcher, a nuclear expert and president of Ploughshares, said: 'We are actually less secure now from the nuclear threat than we were before he started the war, because they still have the material and we still have no greater insight into what they might do with it.' She added that the attack likely increased Tehran's calculus to seek nuclear weapons to prevent such attacks in the future.
According to the IAEA, about 200kg of HEU, enriched to 60% purity, is stored in deep shafts under a mountain near Isfahan. Trump was briefed on a Pentagon proposal to secure and extract the stockpile, which would have involved taking control of the area, flying in equipment, and building a runway—an operation requiring hundreds or thousands of troops and exposing them to high risks. Trump's remarks suggest he judged the risks too high. The HEU stockpile itself resulted from Trump's 2018 withdrawal from the multilateral nuclear deal.
