Iran has sealed and mined access points to an Iranian uranium cache of near-bomb-grade material, complicating US efforts to remove or destroy it, CNN reported. The report said Iran had collapsed tunnels and placed explosive mines near entrances in recent weeks.
The measures made access to about half a ton of highly enriched uranium more difficult than it was a month earlier.
The material sits at the centre of talks between Tehran and Washington. A senior US administration official told reporters that any deal would require Iran to turn over enriched uranium. Additionally, any deal would require on-site destruction and removal, CNN reported.
The International Atomic Energy Agency has said most of Iran’s highly enriched uranium is likely at the Isfahan nuclear complex in central Iran.
IAEA Director General Rafael Mariano Grossi said in March that almost half of Iran’s uranium enriched up to 60% was stored in an Isfahan tunnel complex. He said it was probably still there.
CNN said Iran’s United Nations delegation and the White House did not immediately respond to requests for comment.
US and Iranian officials have offered conflicting accounts of a tentative deal, and its final terms remain unclear.
Scott Roecker, former head of the National Nuclear Security Administration’s Office of Nuclear Material Removal, told CNN that mined or collapsed tunnels would complicate any effort to retrieve highly enriched uranium. He said negotiators would need Iran to provide the full inventory for verification.
Read: Iran US Deal Reaches Final Approval Stage In Tehran
Trump paused a proposed military operation in May to seize the material because officials judged it too risky, CNN previously reported.
Any removal would require extensive excavation, de-mining, and specialised uranium-handling equipment.
The negotiators still expected more technical talks if Tehran and Washington signed an agreement. Trump told reporters earlier this month that removal would take at least two weeks.
