The US has bombed three nuclear sites in Iran, President Donald Trump has announced.

Writing on his social media platform Truth Social, Trump said the US had executed three “very successful attacks” on the sites at Fordow, Natanz and Esfahan.

“All planes are now outside of Iran airspace,” he wrote.

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“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.”

The announcement was shortly after confirmed in a statement from the White House on Saturday local time.

Earlier the same day, two US official told Reuters that B-2 bombers were being deployed to Guam.

While they did not disclose details on the numbers of B-2s, which can carry weapons designed to destroy targets deep underground, one of the officials said, at the time, no orders had yet been given to move the aircraft beyond Guam.

Trump had only days ago given himself a two-week deadline to decide if US forces will strike Iran.

The White House had insisted the delay was to give Iran leadership a chance to negotiate and shut down its nuclear program.

Foreign Minister Penny Wong on Friday said the Australian military is being called in to help Australians trying to leave Iran and Israel.

Wong stressed the government was not sending in the Defence Force in combat roles, but only to assist citizens and residents.

“We are sending defence assets to help Australians — they are not there for combat,” Wong said.

“I wish that we had more capacity to assist, but the difficult reality is, the situation on the ground is extremely unstable.”

The defence personnel and aircraft are part of contingency plans to help Australians leave if and when the now-closed airspace in Israel and Iran reopens.

Some Iranian consulate staff have been sent to the closest land crossing in Azerbaijan to help Australians still in the nation.

United States Senator Bernie Sanders was speaking live on a tour in Tulsa, Oklahoma, when the breaking news came in, reading Trumps statement live to the audience who began chanting “no more war”.

“The American people do not want more war, more death,” Sanders said.

“It might be a good idea if we concentrate on the problems that exist (in America) than getting involved in another war we do not want.”

Iranian state media outlet FARS News said residents of Qom, a city about 87 miles south of Tehran, heard several explosions outside their city, according to CNN.

The Fordow nuclear plant is located close to Qom, and is said to be built into a mountainside.

The air defence system at Fordow was activated shortly before the strike, FARS reported.

Trump to address the nation

Trump announced in a second post he will deliver an address to the nation at 10pm local time from the White House, to discuss what he called a “very successful military operation”.

“I will be giving an Address to the Nation at 10:00 P.M., at the White House, regarding our very successful military operation in Iran,” Trump wrote in a Truth Social post.

“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.”