U.S. President Donald Trump has repeatedly issued threats to bomb Pickaxe Mountain, an under-construction Iranian nuclear site buried deep under a mountain.

“We’ll be hitting that area … probably pretty soon. And there’s not a thing they can do about it,” Mr. Trump said on Tuesday (July 21, 2026) talking to journalists at the Oval Office, Washington.

This fortified site has thus become a focal point of tension as the situation escalates over the Strait of Hormuz.

What is Pickaxe Mountain and why is it targeted by Trump?

The site, referred to as Kuh-e Kolang Gaz, or “Pickaxe Mountain,” is situated to the south of Iran’s Natanz nuclear enrichment facility. This site was targeted by the United States during Operation Midnight Hammer, part of the 12-day conflict between Iran and Israel in 2025. However, Pickaxe Mountain has remained unscathed while Iran continues its excavation activities in the area.

The Pickaxe Mountain site, located about 225 kilometres south of Tehran, next to Natanz, has been constructed in response to earlier attacks on Iran’s nuclear infrastructure. Natanz, which includes both above-ground and underground facilities, has raised international concerns since it became known two decades ago. Repeated sabotage attacks, notably one attributed to Israel that destroyed a centrifuge manufacturing site, prompted Iranian officials to develop the Pickaxe Mountain site.

Also read: U.S.-Iran tensions LIVE updates

Protected by anti-aircraft batteries, fencing and Iran’s paramilitary Revolutionary Guard, the facility sprawls across 2.7 square kilometres in the country’s arid Central Plateau. It has multiple entrances visible from satellite images.

Recently, President Trump mentioned Pickaxe Mountain as a possible target for bombing, especially since tensions between Iran and the U.S. are rising. While speaking with Lebanese President Joseph Aoun, Mr. Trump highlighted Iran’s stockpile of enriched uranium and said that the U.S. would likely attack that area soon. He has also acknowledged the possibility that Iran may have moved centrifuges there, potentially at a depth that would challenge even the most powerful bombs in America’s arsenal. Moreover, its location, protected from prior military strikes, allows Iran to advance its nuclear program beyond the capabilities of standard airstrikes.

Why did Iran build Pickaxe Mountain?

According to AP reports, the size of the construction project indicates Iran will likely be able to use the underground facility to enrich uranium as well as to build centrifuges.

Centrifuges, tube-shaped devices arranged in large cascades of dozens of machines, rapidly spin uranium gas to enrich it. Additional cascades spinning would allow Iran to quickly enrich uranium under the mountain’s protection.

Is this nuclear facility functional?

The Institute for Science and International Security (ISIS), in its report, said its assessment “is that the facility is not yet ​operational, but construction continues”, and that it was unclear when it could be operational, based on satellite imagery alone.

“It is also unclear ​if Iran still plans on ⁠installing a large-scale assembly facility, given the destruction of Iran’s centrifuge programme, including Iran’s ability to make centrifuge components needed for an assembly plant.

Also read| Far from over: On the U.S.-Iran conflict

“Nonetheless, if Iran starts to rebuild its centrifuge manufacturing capability, it could plan to install a smaller centrifuge assembly facility in Pickaxe Mountain able to serve a nuclear weapons program,” ISIS said.

What happens if the Pickaxe Mountain site is attacked?

An attack on the nuclear site might drive Iran’s nuclear operations even deeper underground, completely ending diplomatic oversight and accelerating their pursuit of a weapon.

The U.S. and Iran signed an interim memorandum of understanding on July 17 that suspended military operations, called for the reopening of the Strait of Hormuz and set a 60-day timeframe for negotiating a permanent agreement, including terms covering Iran’s nuclear program. However, the memorandum did not clarify how the future management of the Strait of Hormuz would be handled.

(With Agencies inputs)

The United Nations nuclear watchdog has been unable to inspect nuclear facilities in Iran affected by the war last June, according to a confidential report by the UN nuclear watchdog circulated to member states.

Also read: West Asia war developments on June 9, 2026

The International Atomic Energy Agency (IAEA) reported that it “cannot provide any information on the current size, composition or whereabouts of the stockpile of enriched uranium in Iran or whether Iran has suspended all enrichment-related activities.”

The IAEA warned that it was “unable to discharge its safeguards responsibilities” that it has under the Safeguards Agreement of the Nuclear Non-Proliferation Treaty, adding that it is “indispensable and urgent” for Tehran to implement its obligations under that Treaty.

The only nuclear facility inspected in Iran by IAEA inspectors since the last report in February has been the Bushehr nuclear power plant, which was visited on June 1-3. The reactor currently running at Bushehr uses uranium from Russia enriched to 4.5 per cent, a low level needed for power generation in such plants.

The confidential report comes as tensions have flared in West Asia

Iranian drones heavily damaged a passenger terminal at Kuwait’s main airport on Wednesday (June 3, 2026), killing one person, wounding dozens of others and briefly closing the airfield — the latest in back-and-forth attacks by Iran and the U.S. that test a fragile ceasefire.

According to the IAEA, Iran maintains a stockpile of 440.9 kg of uranium enriched up to 60% purity — a short, technical step away from weapons-grade levels of 90 per cent.

That stockpile could allow Iran to build as many as 10 nuclear bombs, should it decide to weaponise its programme, IAEA director general Rafael Grossi warned in a recent AP interview. He added that it doesn’t mean that Iran has such a weapon.

Such highly enriched nuclear material should normally be verified every month, according to the IAEA’s guidelines.

The report said Grossi reiterates his “full support for the negotiations underway aimed at finding a mutually acceptable solution to issues related to Iran’s nuclear programme, and his readiness … to support an eventual agreement.”

Talks have dragged on for weeks as mediators seek a more enduring truce in the war, now in its fourth month. They are increasingly strained by Israel’s broadening war with Iran-backed Hezbollah militants in Lebanon.

Iran maintains its hold on the Strait of Hormuz — a crucial waterway for the world’s oil and natural gas and related products like fertilizer — and the US continues its blockade of Iranian ports. Global fuel prices remain high, and the effects of the conflict are felt well beyond the region.

Iranian President Masoud Pezeshkian on Saturday (September 27, 2025) said Washington had demanded that Tehran hand over all its enriched uranium in return for a three-month reprieve from sanctions, rejecting this as “unacceptable”.

The United States “wants us to hand over all our enriched uranium to them, and in return they would give us three months” exemption from sanctions,” Mr. Pezeshkian told reporters in New York before leaving for Tehran. “This is by no means acceptable.”