Fresh Activity Reported at Iran’s Buried Nuclear Site as Trump Warns Tehran Not to ‘Get Cute’

Fresh satellite imagery indicates that Iran has strengthened defenses around the entrances to tunnels at Pickaxe Mountain, a heavily fortified, nuclear-related site that President Donald Trump has repeatedly threatened to target. The development came as Russia and China vetoed a U.S.-backed United Nations resolution seeking to keep international oversight of sanctions against Tehran in place.

In a report published Thursday, the Institute for Science and International Security said images captured Sept. 11 show earthen barriers still blocking roads to the western tunnel entrances at Pickaxe Mountain, located near Iran’s Natanz nuclear complex. According to the institute, the restricted access suggests the site is not being used for routine operations, although important equipment or materials may still be stored underground.

Researchers also observed fresh soil covering one of the western portals and a nearby group of entrances constructed in 2007. The additional earth appears to increase the protective layer over the tunnel openings, potentially making them more resistant to airstrikes.

The assessment was released roughly a week after Trump issued another public warning concerning activity at Pickaxe Mountain.

“We notice there’s a little activity at Pickaxe,” Trump told reporters last week. “I would advise Iran not to get cute because we will have to hit them very hard.”

Trump has repeatedly suggested that the United States could strike the facility. During a July 28 interview on “Fox & Friends” that was promoted by the White House, he said Washington was closely monitoring Pickaxe and knew “exactly what’s going on.” If diplomacy failed, he added, the U.S. could “take out Pickaxe.”

Pickaxe Mountain is located about two kilometers from Natanz and contains several tunnel openings leading to a deeply buried underground site. Iran began building the complex in 2020 after sabotage damaged an advanced centrifuge assembly center at Natanz. Iranian officials later said the replacement facility was intended to support production of advanced centrifuges. Analysts believe parts of the installation could lie at least 100 meters underground, while Tehran maintains that no nuclear work is taking place there.

Behnam Ben Taleblu, senior director of the Iran program at the Foundation for Defense of Democracies, told News Outlet that some experts believe the opportunity to carry out a simple, direct attack on Pickaxe Mountain may have disappeared.

“The window to strike Pickaxe Mountain, according to some, has already expired because the regime has dug an underground nuclear facility several times deeper than Fordow,” Ben Taleblu said. He nevertheless argued that the United States still has military choices if destroying the buried complex outright is not feasible.

Washington, he said, could rely on tactics historically used against deeply buried and heavily fortified sites by targeting their access points. Burying the entrances, he argued, could also increase the political cost for Iran if it attempts to excavate and restore the facility.

“While there may not be the perfect munition just yet, Uncle Sam always has a bigger bomb,” Ben Taleblu said. “And in the meantime, what they can do is show that they mean business by burying the entrances.”

The new imagery from Pickaxe Mountain was accompanied by evidence that Iran is rebuilding another strategically sensitive site.

In a separate Thursday report, the institute said reconstruction at Taleghan 2, inside the Parchin military complex southeast of Tehran, was advancing rapidly. Vantor Technologies imagery from Sept. 13 showed a large tarp covering the damaged hardened structure, apparently shielding construction activity from satellite and aerial surveillance. Dump trucks, bulldozers, concrete machinery and cranes were visible nearby.

The institute also reported the installation of new concrete reinforcement that could make the facility more resistant to air attack. Israel struck Taleghan 2 in October 2024 and again in March 2026, after Iran had rebuilt and further fortified the site. The institute said the purpose of the facility remains uncertain.

The latest indications of military construction emerged as a separate dispute over Iran intensified at the United Nations.

Russia and China on Thursday blocked a U.S.-drafted Security Council resolution that would have extended the mandate of the Panel of Experts assisting the 1737 Iran Sanctions Committee through September 2027. The proposal received 11 votes in support, while Pakistan and Somalia abstained.

The panel investigates alleged sanctions violations and reports on implementation. The dispute reflects a deeper split over whether UN sanctions suspended under the 2015 nuclear agreement were legally restored through the “snapback” mechanism. Most Council members maintain that the sanctions and related monitoring structures were revived, while Russia and China reject the legal and procedural validity of that position.

A day before the vote, U.S. Ambassador to the U.N. Mike Waltz told reporters in New York that Washington considers the sanctions legally restored.

“The snapback sanctions… occurred, the United States and this U.N. Security Council followed appropriate procedures for that to occur,” Waltz said Wednesday at a news conference attended by News Outlet. “Those sanctions are in place and we expect those who are a party to fully enforce those sanctions.”

Waltz said the expert panel is important because sanctioned companies and individuals can attempt to evade restrictions by changing names and corporate structures.

“The president has been clear, and the world community has been clear with resolution after resolution, that the Iranian regime cannot have a nuclear weapon,” Waltz said.

Thursday also brought fresh U.N. scrutiny of both Washington and Tehran. An independent U.N. fact-finding mission said it had reasonable grounds to believe two U.S. strikes on civilian sites in Iran in February constituted war crimes, while separately concluding that Iranian authorities committed crimes against humanity during their crackdown on anti-government protests. The mission is investigative rather than judicial, and its findings do not themselves constitute criminal judgments.

News Outlet reached out to the Iran U.N. mission for comments but didn’t receive them in time for publication.