CNN reported that US officials assess that Iran plans to use the “Pickaxe Mountain" nuclear site, buried beneath granite, as a shelter for its nuclear program.

The assessment follows a report by a group of analysts who reviewed six years of satellite imagery and identified a “surge in construction" at the site.

The United States is reportedly considering ways to strike underground facilities.

US President Donald Trump warned on Friday that the United States could soon strike Pickaxe Mountain.

Speaking to reporters in the Oval Office, Trump reiterated his position that Iran must not obtain a nuclear weapon.

"Iran will not have a nuclear weapon," he said, before adding, "We may hit Pickaxe very soon...if there was anything going on with Pickaxe."

Trump was also asked about comments made Thursday by Vice President JD Vance, who said he would not characterize the ongoing conflict with Iran as a "war".

With the United States having resumed strikes against Iranian targets for the first time in recent weeks, Trump was asked how he would describe the confrontation.

"A lot of people don't call it a war. I call it a military conflict because it's small potatoes for us. It's not a big thing. We did Venezuela and we did this. In Venezuela we lost nobody, and in this we lost 18 people. And Vietnam - you lost a hundred thousand people," he replied.