US President Donald Trump urged Iran on Friday to "make a deal," warning that there will be more "death and destruction" after Israel launched deadly strikes targeting Iranian nuclear facilities.
His comments on his Truth Social platform came after Israel pounded Iran in a series of air raids on Friday, striking 100 targets.
The operation killed senior figures -- among them the armed forces chief and top nuclear scientists -- and Iran has called Israel's wave of strikes a "declaration of war."
On Friday morning, Trump said: "I gave Iran chance after chance to make a deal."
He added that Israel -- which Trump has aligned Washington to since his return to the White House -- has a lot of weapons thanks to the United States and "they know how to use it."
"There has already been great death and destruction, but there is still time to make this slaughter, with the next already planned attacks being even more brutal, come to an end," Trump said on his Truth Social platform.
"Iran must make a deal, before there is nothing left... JUST DO IT, BEFORE IT IS TOO LATE," he said.
Trump earlier told Fox News he had been made aware of the Israeli strikes before they happened, and stressed that Tehran "cannot have a nuclear bomb," the US broadcaster said.
He also said that "we are hoping to get back to the negotiating table," according to Fox News.
During Trump's first term, he pulled the United States out of a landmark agreement to relieve sanctions on Iran in return for curbs on its nuclear program.
Fox News also reported that Trump's administration reached out to at least one key Middle Eastern ally to acknowledge that the strike was going to happen, but said the United States was not involved.
"Trump noted the US is ready to defend itself and Israel if Iran retaliates," Fox News said.
Secretary of State Marco Rubio said earlier Thursday that the United States was "not involved in strikes against Iran and our top priority is protecting American forces in the region."
"Let me be clear: Iran should not target US interests or personnel."
Security concerns had risen since Trump said on Wednesday that Us personnel were being moved out of the region because "it could be a dangerous place" and that Tehran would not be allowed to develop a nuclear weapon.
Washington and Tehran on Thursday had announced plans for another round of talks on Sunday in Oman between US special envoy Steve Witkoff and Iranian Foreign Minister Abbas Araghchi.
A U.S. official told news agency Reuters late on Thursday that the talks were still on.
"We still intend to have talks Sunday," the official said, without elaborating.
Trump will be attending a National Security Council meeting Friday morning.
Trump makes G7 summit return in Iran crisis
Trump, whose second term has been devoted to going it alone, makes his return to the Group of Seven in crisis mode after Israel attacked Iran.
The G7 summit starting Sunday in the Canadian Rockies town of Kananaskis marks the first major global gathering of Trump's second term, in which he has been even more brash in shattering diplomatic norms.
Looking to avoid a dust-up, Canadian Prime Minister Mark Carney had set the agenda on largely uncontroversial themes such as building global supply chains for critical minerals.
That agenda could now be upended as Israel launched a massive military campaign against Iran on Friday, saying it was taking pre-emptive action against its adversary's contested nuclear program.
The Trump administration has closely aligned the United States with Israel, taking aim even at close allies who criticize its offensive in Gaza.
But Israeli Prime Minister Benjamin Netanyahu openly defied Trump, who hours earlier had called for a diplomatic solution and whose friend and roving envoy Steve Witkoff had been due to hold new talks with Iran on Sunday just as the G7 opened.
A senior Canadian official said there would be no attempt at the G7 to reach consensus on a joint communique on the issues of the day and that leaders instead would be asked to endorse "short, action-oriented statements."
"Of course it would be desirable for a summit statement to be issued, but as the summit is being held in a very complex international situation, I believe that the unity of the G7 should be given the highest priority," Japanese Foreign Minister Takeshi Iwaya said.