United States President Donald Trump says Washington may strike Iran’s Pickaxe Mountain “very soon”, in just the latest in a series of threats he has made against the heavily fortified underground site located next to the bombed-out Natanz enrichment complex.

Just hours after he made that threat, an Iranian oil tanker off Kharg Island was struck by four US missiles, according to Iranian news outlet Khabar Fouri. Kharg Island is the main hub for Iran’s oil exports, handling about 90 percent.

Trump made the threat against Pickaxe Mountain as he was speaking to reporters in the Oval Office on Friday, saying the US knows “everybody that’s moving at Pickaxe” and across Iran.

His remarks echoed a similar threat he made back in mid-July, when he stated on the Hugh Hewitt Show: “We’re going to take out Pickaxe Mountain. Tell the Iranians to be ready … We’ll probably give Pickaxe a shot relatively soon.”

The latest threat comes more than six months into the war that the US and Israel launched on Iran on February 28, amid mixed messages about the war from the Trump administration.

On Friday, Trump sought to downplay the war in Iran, calling it “small potatoes”, while a day earlier, at a White House news briefing, Vice President JD Vance appeared to suggest the conflict had cooled and to shrug off an alleged US strike on a wedding in southern Iran with “sometimes things happen“.

At a White House briefing this week, Vance said of the conflict with Iran that he “wouldn’t call it a war” and claimed there was “no active shooting right now”.

But the US and Iran have exchanged attacks this week, including a US hit close to Iran’s oil infrastructure on Kharg Island.

Meanwhile, talks related to Iran’s nuclear programme have remained in limbo since a 60-day negotiating window expired in mid-August without a deal.

Iran says it is not undertaking any work at the Natanz nuclear site.

Its Khatam al-Anbiya central military headquarters has warned that bombing the nearby mountain would amount to a renewal of war across the region, at a time when the Trump administration would prefer to keep the war contained before pivotal mid-term elections.

So why has Pickaxe Mountain become the latest focus of Trump’s threats – again?

What is Pickaxe Mountain?

Known in Iran as Kuh-e Kolang Gaz La, the site sits roughly 220km (140 miles) south of the capital Tehran, in Isfahan province, and just 2km (1.2 miles) from the Natanz enrichment plant.

US intelligence reports indicate that the facility has been excavated deep inside the mountain, beneath hundreds of metres of solid granite rock, to protect it from powerful bombs designed to penetrate bunkers.

The main chambers are thought to lie at least 100 metres (330ft) underground.

Some Western analysts have speculated that the mountain was intended to house an undeclared enrichment plant, a hedge against attacks on Iran’s known facilities.

The Institute for Science and International Security, which tracks the site by satellite, has assessed that it is still under construction and not yet operational.

However, Iran has always maintained that it is developing a nuclear power programme only, and does not have plans to build a nuclear weapon.

Why does Pickaxe Mountain matter?

Because it is intact.

Pickaxe Mountain was left alone during the US’s June 2025 strikes on Fordow, Natanz and Isfahan at the end of the 12-day Israel war on Iran, and has escaped the current war almost entirely; the Institute for Science and International Security has recorded only the destruction of a vehicle on a nearby spoil pile.

With Iran’s centrifuge manufacturing base and enrichment halls at other sites damaged in the war, analysts see the tunnels as the most obvious place for Tehran to rebuild: For component production, assembly or enrichment of uranium.

The Wall Street Journal reported in July that Israel had passed Washington intelligence suggesting thousands of centrifuges had been moved inside the facility late last year, a claim the US has not confirmed.

Trump has been less alarmist than Israel.

Centrifuges only matter if there is uranium to put through them; the machines concentrate uranium gas, and without a supply of it they cannot produce anything.

How much damage has been done to Iran’s nuclear sites?

According to most estimates, a considerable amount.

The European Council on Foreign Relations estimates that the 2025 strikes likely destroyed many of the roughly 18,000 centrifuges then operating at Iran’s Natanz and Fordow facilities, along with several centrifuge production sites and Ardakan, Iran’s only yellowcake milling plant. Yellowcake is powdered uranium concentrate obtained from milled uranium ore.

Nearly 4,000 additional centrifuges were installed but idle at the time; however, they may have survived the strikes.

The International Atomic Energy Agency (IAEA) confirmed further damage to the entrance buildings of Natanz’s underground enrichment plant in March 2026, although it detected no additional impact on the plant itself.

The Institute for Science and International Security reported in June that tunnel entrances at all three main sites remain sealed, that there is no evidence of any enrichment taking place, and that the centrifuge programme still appears to have been destroyed.

Didn’t Trump say Iran’s nuclear sites had already been destroyed?

Yes. After the June 2025 attacks, Trump said the three sites had been “completely and totally obliterated”.

However, just days later, a leaked preliminary US Defence Intelligence Agency assessment concluded that the sites had been significantly damaged but not destroyed, estimating that the strikes had set Iran’s nuclear programme back by less than six months.

The situation today remains unclear.

Iran is currently believed to be holding about 440kg (970lb) of uranium enriched to 60 percent. A 90-percent threshold of enriched uranium is needed to produce a nuclear weapon.

No inspector has entered the bombed sites, and Trump’s framing has shifted from “obliteration” to a promise to hit any site where Iran is “even thinking about nuclear”.

What do we know about Iran’s nuclear programme?

Less than at any point in two decades.

Just before the US-Israel attacks on Iran in June 2025, the IAEA verified about 10 tonnes of enriched uranium in total, including the 440kg stockpile enriched to 60 percent.

In theory, this amount of enriched uranium – should it be enriched to 90 percent – is enough to produce more than 10 nuclear warheads, IAEA chief Rafael Grossi told Al Jazeera in early March. It is unclear where this stock may be, however.

Iran suspended cooperation with the agency after the strikes, and the IAEA now says it has no way to report on the size, location or composition of that stockpile, though it believes much of the 60-percent material is bottled up in tunnels at Isfahan.

On Friday, Trump claimed again that the US had prevented Iran from developing a nuclear weapon, arguing that Washington’s intervention had protected Israel and the wider Middle East.

Tehran insists the programme is peaceful, and has dismissed Washington’s focus on Pickaxe Mountain as a manufactured pretext for attacking it.