Iran Moves Nuclear Stockpile Underground as US Strike Fears Mount

Iran has taken extensive measures to secure its highly enriched uranium stockpile amid fears of a potential US military strike. According to CNN, citing five sources familiar with US intelligence, Iranian forces have dug several underground tunnels in recent weeks and planted explosive mines at the entrances.

Intelligence sources state that reaching Iran's nearly half-ton (900 pounds) stockpile of weapons-grade uranium has become significantly more difficult, risky, and time-consuming. These defense measures follow public indications from US President Donald Trump that he could order the military to seize the material.

Analysts warn that this new underground network complicates ongoing negotiations between Washington and Tehran. Specifically, it creates severe logistical hurdles for a proposed agreement aimed at removing and destroying Iran's enriched uranium.

The White House and Iran’s United Nations mission did not immediately respond to requests for comment.

Securing the uranium remains a primary US priority in broader talks to permanently reopen the Strait of Hormuz and resolve the regional standoff. A senior Trump administration official stated on Friday that both sides are nearing a memorandum of understanding (MOU). Under the proposed framework, Iran would hand over its enriched uranium to be destroyed on-site or removed from the country.

However, significant discrepancies remain between US and Iranian statements regarding the exact terms of the deal. Tensions flared further after a purported text of the agreement was leaked to a semi-official Iranian news outlet, drawing public anger from President Trump on social media.

Nuclear experts note that extracting the uranium under current conditions presents extreme risks. Scott Roker, former head of the US National Nuclear Security Administration’s (NNSA) Office of Nuclear Material Removal, warned that the heavily mined tunnels allow Tehran to complicate verification. Iran could claim certain stockpiles are inaccessible, making full accounting nearly impossible.

International intelligence suggests most of the material is secured within fortified or collapsed tunnels at the Isfahan nuclear complex in central Iran, with remaining amounts spread across secondary facilities. CNN previously reported that a US military operation to forcibly seize the material in mid-May was aborted due to extreme tactical risks. President Trump later acknowledged those risks publicly, noting that forcing entry into the monitored sites was too hazardous. However, intelligence officials believe his public remarks may have inadvertently prompted Iran to fortify its positions further.

Even if a preliminary deal is signed next week, executing it will require intense technical orchestration. Removing the material could necessitate deploying specialized mobile processing units managed by the NNSA. Signaling serious preparations, top US negotiators Jared Kushner and Steve Witkoff visited the Oak Ridge National Laboratory in Tennessee earlier this month to consult with a newly formed 100-expert nuclear task force. Experts warn that even with the world's leading specialists, clearing the mines and securing the material will take weeks.