Donald Trump watches the US strikes from the Situation Room at the White House - REUTERS

The US has bombed three of Iran’s nuclear facilities, Donald Trump has announced, in an assault that threatens to bring the two countries to war.

The US president authorised the bombings of the underground Fordow plant, one of the country’s key nuclear sites, and two other facilities in the early hours of Sunday morning, calling it a “successful attack”.

“We have completed our very successful attack on the three nuclear sites in Iran, including Fordow, Natanz, and [Isfahan],” Mr Trump said on Truth Social.

“All planes are now outside of Iran air space. A full payload of bombs was dropped on the primary site, Fordow. All planes are safely on their way home. Congratulations to our great American Warriors.

“There is not another military in the World that could have done this. NOW IS THE TIME FOR PEACE! Thank you for your attention to this matter.”

In what is the most consequential decision of Mr Trump’s presidency so far, the assault signals a significant escalation in the conflict with Tehran.

Pressure had been mounting on the US to intervene in the escalating conflict in support of Israel, and to force Iran’s leaders to end its nuclear programme.

Amid the prodding of Israeli officials and many Republican lawmakers, Mr Trump had approved plans for a US strike on Iran earlier this week but had not yet given a final order.

On Saturday, the green light was given to strike the Fordow plant, Iran’s most heavily fortified and primary nuclear facility.

It came after officials revealed earlier that day that B-2 stealth warplanes and refuelling tankers had left their Missouri base for the Pacific base of Guam.

The plant, 20 miles from the central city of Qom, is considered so naturally protected that there is just one weapon in the world able to blow it up.

The US’s 30,000lb GBU-57F/B Massive Ordnance Penetrator bomb, or “Mop”, can penetrate around 60 metres underground before exploding.

Officials fear weapons-grade uranium and hazardous raw materials were being manufactured at the site, and experts had warned a strike could have severe effects.

B-2 stealth bombers armed with six of the bunker-busting bombs were used in the strike, Fox News reported. The White House and Pentagon did not immediately elaborate on the operation.

The weapon is thought to be able to penetrate through 61 metres of concrete and is considered the only weapon able to directly threaten the site itself.

It can only be dropped by a B-2 stealth bomber, which can carry two at a time.

The bomb is designed to penetrate and detonate at the maximum possible depth to neutralise interred threats such as bunkers.

The president had spent Friday night and much of Saturday at his golf club in Bedminster, New Jersey.

But in a sign of a fast developing situation, flew back to the White House just before 5pm. He didn’t speak to his travelling press pool at any point.

Announcing he would address the nation at 10pm Eastern Time, Mr Trump said: “This is an HISTORIC MOMENT FOR THE UNITED STATES OF AMERICA, ISRAEL, AND THE WORLD. IRAN MUST NOW AGREE TO END THIS WAR. THANK YOU!”

The strikes present a risky gambit to weaken a longtime foe amid Tehran’s threat of reprisals that could spark a wider regional conflict.

Pete Hegseth and Marco Rubio watch the strikes unfold - REUTERS

For Mr Trump, the decision to strike is a political gamble. He won the White House on the promise of keeping America out of costly foreign conflicts and scoffed at the value of American interventionism.

He told reporters on Friday that he was not interested in sending ground forces into Iran, saying it’s “the last thing you want to do.” He had previously indicated that he would make a final choice over the course of two weeks.

Iran’s Supreme Leader Ayatollah Ali Khamenei warned the United States on Wednesday that strikes targeting the Islamic Republic will “result in irreparable damage for them.”

And Iranian Foreign Ministry spokesman Esmail Baghaei declared “any American intervention would be a recipe for an all-out war in the region.”

Israel preparing for long war

Mr Trump has vowed that he would not allow Iran to obtain a nuclear weapon, and he had initially hoped that the threat of force would bring the country’s leaders to give up its nuclear program peacefully.

The Israeli military said Saturday it was preparing for the possibility of a lengthy war, while Iran’s foreign minister warned before the US attack that American military involvement “would be very, very dangerous for everyone.”

The prospect of war now looms.

Iranian-backed Houthi rebels in Yemen have warned they would resume attacks on US vessels in the Red Sea if the Trump administration joined Israel’s military campaign.

The Houthis paused such attacks in May under a deal with the US.

The US ambassador to Israel announced that the US had begun “assisted departure flights,” the first from Israel since the Hamas-led attack on October 7, 2023, that sparked the war in Gaza.

A protester outside the White House on Saturday night - EPA

White House press secretary Karoline Leavitt said Thursday that M Trump planned to make his decision on the strikes within two weeks. He chose to strike just two days later.

The president appears to have made the calculation at the prodding of Israeli officials and many Republican lawmakers.

His decision for direct intervention comes after his administration made an unsuccessful two-month push, including with high-level, direct negotiations with the Iranians, aimed at persuading Tehran to curb its nuclear programme.

Trump wagers that diplomacy has failed

For months, Trump said he was dedicated to a diplomatic push to persuade Iran to give up its nuclear ambitions.

And he twice, in April and again in late May, persuaded Israeli Prime Minister Benjamin Netanyahu to hold off on military action against Iran and give diplomacy more time.

The US in recent days has been shifting military aircraft and warships into and around the Middle East to protect Israel and U.S. bases from Iranian attacks.

All the while, Trump has gone from publicly expressing hope that the moment could be a “second chance” for Iran to make a deal to delivering explicit threats on Khamenei and making calls for Tehran’s unconditional surrender.

“We know exactly where the so-called ‘Supreme Leader’ is hiding,” Trump said in a social media posting. “He is an easy target, but is safe there - We are not going to take him out (kill!), at least not for now.”

Sir Keir Starmer had hoped that an intervention at the G7 would persuade the US president from joining the conflict.

Diplomatic sources told The Telegraph that Washington had also been told that military intervention could trigger a wave of terror attacks by sleeper cells across Europe.

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