US reportedly assured Iran that strikes on nuclear sites were a 'one-off'

The US gave Iran advance notice before launching strikes on three of its nuclear facilities, according to a report on Sunday, in what appears to have been a calculated move to avoid full-scale war.

Speaking to the London-based outlet Amwaj Media on condition of anonymity, a high-ranking Iranian official said the Trump administration informed Tehran that it did not seek an all-out confrontation and would only launch a 'one-off' strike on the Fordow, Natanz and Isfahan nuclear sites.

US Defence Secretary Pete Hegseth appeared to partially confirm this later on Sunday, when he said that the US “does not seek war” with Iran in the aftermath of the surprise overnight attack overnight. 

“This mission was not and has not been about regime change,” Hegseth added.

 US Chairman of the Joint Chiefs of Staff General Dan Caine said the goal of the operation — destroying nuclear sites in Fordo, Natanz and Isfahan — had been achieved. 

“Final battle damage will take some time, but initial battle damage assessments indicate that all three sites sustained extremely severe damage and destruction,” Caine said.

The Iranian source told Amwaj that the sites had been evacuated in advance and that "most" of Iran's enriched uranium stockpile had been moved to secure locations.

While some infrastructure was hit, the nuclear programme's core assets were largely preserved, the source added

It initially appeared however that the US into Israel’s ongoing war on Iran.

On 21 June, President Donald Trump declared that the three nuclear facilities had been "completely and totally obliterated," adding that "if peace does not come quickly, we will go after other targets with precision, speed and skill".

While the White House has framed the strikes as decisive and limited in scope, the decision to give Tehran prior warning suggests an attempt to mirror the pattern seen in early 2020, when Iran responded to the US assassination of Qassem Soleimani with a symbolic missile barrage against American bases in Iraq.

According to reports, the operation was carried out without the use of US military bases in the Gulf region. Instead, three B-2 bombers reportedly flew from the United States to drop six 30,000-pound Massive Ordnance Penetrator (MOP) buster bunker bombs on the Fordow enrichment site.

Two bombs were aimed at each of the two main entrances, with another two targeting the facility’s ventilation system.

In parallel, a US submarine is believed to have launched 30 Tomahawk cruise missiles targeting Natanz and the Isfahan nuclear complex - both of which had already been hit by Israeli airstrikes in recent days.

Iran has confirmed that all three facilities were struck but has released few additional details. In a statement, the Atomic Energy Organisation of Iran (AEOI) condemned the bombings as a "brutal act" and accused the UN's nuclear watchdog of failing to prevent what it described as a violation of the Non-Proliferation Treaty.

Despite Trump’s claim that the strikes had effectively neutralised Iran’s nuclear programme, independent verification remains incomplete. Analysts have noted that Fordow lies 80 to 90 metres underground, requiring multiple MOP strikes in the same crater to achieve total destruction.

With Iranian leadership already under pressure from sustained Israeli bombardment, the advance warning from Washington may have been intended to give Tehran a diplomatic off-ramp. However, a full Iranian response - whether symbolic or strategic - may still be in the works.