President Donald Trump called the bombing of three nuclear facilities in Iran a "spectacular military success".
He called on Iran to quickly bring peace or said the US would go after other targets with "speed" and "precision".
"This cannot continue. There will be either peace or there will be tragedy for Iran, far greater than we have witnessed over the last eight days," Trump said in an address to the nation from the White House.
Israel initially attacked Iran earlier this month, while the Americans and the Iranians were in nuclear talks. Trump urged Iran to continue negotiations, but on Saturday he went ahead with strikes.
Appearing alongside Vice-President JD Vance, Secretary of Defense Pete Hegseth and Secretary of State Marco Rubio, Trump boasted of the mission's success.
