WSJ- Iran moved thousands of uranium-enrichment centrifuges into a fortified network of tunnels beneath Pickaxe Mountain following last year’s war with Israel, according to an Israeli intelligence assessment shared with the United States, the *Wall Street Journal* (*WSJ*) reported in an exclusive report Monday.
- Activity around the mountain has reportedly increased over the past 15 months, including truck movements, reinforced tunnel entrances, and the construction of a wider security perimeter.
- US President Donald Trump has publicly threatened to target Pickaxe Mountain as Washington steps up its military campaign against Iran, describing it as a possible target for a “nice big fat shot” in a 13 July interview.
- Construction at Pickaxe Mountain reportedly began after an explosion damaged a centrifuge-assembly facility at Natanz in 2020, in an incident suspected to have involved sabotage.
- Iran informed the IAEA in 2021 of its intention to have nuclear activity at the site, but has not provided inspectors with access to determine what work is now being carried out there.
- Without access to the site, the agency cannot independently verify whether centrifuges have been transferred there or determine whether any equipment inside the tunnels is being stored, assembled, or used for uranium enrichment.
- Experts estimate that the tunnel complex may extend more than 100 metres beneath solid rock, potentially providing enough space for several nuclear-related facilities.
- Nate Swanson, who served as an Iran director on the US National Security Council under former President Joe Biden, told the *WSJ* that undeclared activity inside a hardened facility raised the possibility of a “covert breakout”—that is, a secret attempt to produce weapons-grade uranium before foreign governments could detect or prevent it.
- Iran denies pursuing nuclear weapons but has accumulated around 450 kilograms of uranium enriched to 60 percent purity—which is far above the level generally required for civilian energy production and close to weapons-grade.
- David Albright, president of the Institute for Science and International Security, an American think tank specializing in nuclear proliferation issues, told the *WSJ* that it was “plausible” Iran had transferred centrifuges into the tunnels.
Israeli intelligence has concluded that Iran relocated thousands of uranium-enrichment centrifuges into a fortified tunnel network beneath Pickaxe Mountain after the 2025 conflict with Israel. This move, reported by the *Wall Street Journal*, raises alarms about Iran's potential to revive its nuclear program.
The assessment indicates that the centrifuges were transferred to the underground site last autumn, following extensive damage to Iran's nuclear facilities during the 12-day war in June 2025. U.S. President Donald Trump has threatened military action against the site, describing it as a target for a “nice big fat shot.”
The Pickaxe Mountain site, located about 220 km south of Tehran, is believed to have a tunnel complex extending over 100 meters beneath solid rock, potentially housing multiple nuclear-related facilities. David Albright, president of the Institute for Science and International Security, stated that it is “plausible” Iran has moved centrifuges into these tunnels.
The International Atomic Energy Agency (IAEA) has not been granted access to the site, preventing verification of the activities occurring there. Nate Swanson, a former U.S. National Security Council director, warned that undeclared activities could lead to a “covert breakout” for weapons-grade uranium production. Iran, while denying any intent to develop nuclear weapons, has amassed around 450 kilograms of uranium enriched to 60 percent purity, nearing weapons-grade levels.
Increased activity around Pickaxe Mountain, including truck movements and reinforced tunnel entrances, has been reported over the past 15 months, indicating heightened efforts to secure the site.
“The underground complex, known in Iran as Mount Kolang, is located 220 km south of Tehran and roughly two kilometres from the Natanz nuclear site. Activity at the site has increased over the past 15 months, including truck movements and reinforced tunnel entrances, while the IAEA has been denied access to verify the intelligence.”
