The fate of Iran's highly enriched uranium stockpile has become a major obstacle in efforts to reach a potential agreement between Washington and Tehran, with experts warning that the material could be sufficient to produce at least 10 nuclear weapons.
According to a report by The New York Times, much of Iran's enriched uranium is believed to be stored deep underground and possibly spread across multiple locations, complicating efforts to locate, secure, or destroy it.
US President Donald Trump has repeatedly said he is determined to prevent Iran from obtaining a nuclear weapon. However, concerns over the location and security of the uranium stockpile have increased the focus on diplomatic negotiations.
US Secretary of State Marco Rubio said sanctions on Iran are linked to its nuclear activities and possession of highly enriched uranium, adding that sanctions relief could be tied to any agreement requiring Tehran to give up those capabilities.
According to the International Atomic Energy Agency, Iran possessed about 970 pounds of uranium enriched to 60% as of February. Experts say material enriched to that level can be converted into weapons-grade uranium within weeks.
The uranium is believed to be stored in canisters that can be easily moved and dispersed among multiple facilities. Much of the stockpile is thought to be located near the Isfahan nuclear complex, a heavily fortified underground site that analysts believe may be difficult to destroy even with advanced bunker-buster bombs.
Satellite imagery reviewed by experts reportedly indicates that Iran has strengthened security around the facility with blocked tunnel entrances, road barriers, and additional defensive measures.
IAEA Director General Rafael Grossi has identified Isfahan as a likely storage location, though experts caution that the exact whereabouts of the uranium remain uncertain.
Analysts also believe smaller quantities may be stored at Natanz, while attention has increasingly focused on the underground Pickaxe Mountain facility. There are concerns that some material could have been dispersed to undisclosed sites.
The IAEA estimates that Iran possesses more than 19,930 pounds of enriched uranium in total. While much of it remains below weapons-grade levels, experts say Iran retains the ability to further enrich the material if its nuclear infrastructure remains intact.