Israeli intelligence believes Iran has relocated thousands of uranium-enrichment centrifuges to a heavily fortified underground complex inside Pickaxe Mountain, a move that could complicate any future military effort to cripple Tehran's nuclear program, according to U.S. and Israeli officials cited by The Wall Street Journal.

The report said Israel shared the intelligence with the United States, assessing that the centrifuges were transferred to the site last fall following the 12-day war in June 2025, during which U.S. and Israeli forces struck Iran's three main nuclear facilities.

According to the officials, the relocation suggests Tehran may be attempting to rebuild or preserve key elements of its nuclear infrastructure after the attacks.

Satellite imagery cited in the report indicates that the Pickaxe Mountain complex has been excavated more than 100 yards (about 90 meters) beneath solid bedrock, making it deeper and more heavily protected than Iran's Fordow uranium enrichment facility and significantly more difficult to destroy through conventional airstrikes.

Iran has said the underground site is intended only for the production and assembly of centrifuges and is not being used for uranium enrichment.

However, Tehran has barred inspectors from the International Atomic Energy Agency (IAEA) from accessing the facility.

IAEA Director General Rafael Grossi has repeatedly called on Iran to explain the nature of its activities at the site and to allow international inspectors access.

The intelligence assessment comes as U.S. President Donald Trump has renewed public attention on the facility.

Last week, Trump described Pickaxe Mountain as "a possible target for a nice big fat shot right near the front door."

"We see no activity there. They're not doing well with their nuclear situation," Trump said. "We'll probably give Pickaxe a shot relatively soon."

Separately, CNN reported earlier this month that recent satellite imagery showed trucks and construction vehicles entering and leaving the underground complex, activity that analysts say could indicate Iran is rebuilding or expanding facilities at the site.

CNN also reported that the activity could potentially violate the U.S.-Iran memorandum of understanding, which requires Iran to maintain the status quo at its nuclear facilities.