WASHINGTON, June 28, 2025 (AFP) - US President Donald Trump said Friday he had saved Iran's Ayatollah Ali Khamenei from assassination and lashed out at the supreme leader for ingratitude, declaring he would order more bombing if the country tried to pursue nuclear weapons.

In an extraordinary outburst on his Truth Social platform, Trump blasted Tehran for claiming to have won its war with Israel and said he was halting work on possible sanctions relief.

The tirade came as Iran prepared to hold a state funeral for 60 nuclear scientists and military commanders who were killed in the 12-day bombing blitz Israel launched on June 13.

Iran says the scientists were among a total of at least 627 civilians killed.

Trump said the United States would bomb Iran again "without question" if intelligence indicated it was able to enrich uranium to military grade.

Iran has consistently denied any ambition to develop a nuclear arsenal.

Trump accused the Iranian leader of ingratitude after Khamenei said in a defiant message that reports of damage to nuclear facilities were exaggerated and that Tehran had dealt Washington a "slap" in the face.

"I knew EXACTLY where he was sheltered, and would not let Israel, or the U.S. Armed Forces, by far the Greatest and Most Powerful in the World, terminate his life," Trump posted.

"I SAVED HIM FROM A VERY UGLY AND IGNOMINIOUS DEATH, and he does not have to say, 'THANK YOU, PRESIDENT TRUMP!'"

Trump also said that he had been working in recent days on the possible removal of sanctions against Iran, one of Tehran's main demands.

"But no, instead I get hit with a statement of anger, hatred, and disgust, and immediately dropped all work on sanction relief, and more," Trump added, exhorting Iran to return to the negotiating table.

Iran has denied it is set to resume nuclear talks with the United States, after Trump said that negotiations were set to begin again next week.

Its government on Friday rejected a request by Rafael Grossi, the director of the UN's International Atomic Energy Agency, to visit facilities bombed by Israel and the United States, saying it suggested "malign intent."

Foreign Minister Abbas Araghchi hit out at Grossi personally in a post on X for not speaking out against the air strikes, accusing him of an "astounding betrayal of his duties."

- 'Beat to hell' -

Asked earlier in a White House press conference whether he would consider fresh air strikes if last week's sorties were not successful in ending Iran's nuclear ambitions, Trump said: "Sure. Without question. Absolutely."

Trump added that Khamenei and Iran "got beat to hell".

The war of words came with a fragile ceasefire holding in the conflict between Israel and Iran.

Speculation had swirled about the fate of Khamenei before his first appearance since the ceasefire -- a televised speech on Thursday.

Khamenei hailed what he described as Iran's "victory" over Israel, vowing never to yield to US pressure.

"The American president exaggerated events in unusual ways, and it turned out that he needed this exaggeration," the Iranian leader said.

It was unclear if Khamenei would attend Saturday's state funeral in Tehran.

The commemorations begin at 8:00 am (0430 GMT) at Enghelab Square in central Tehran, to be followed by a funeral procession to Azadi Square, about 11 kilometres (seven miles) across the sprawling metropolis.

In a televised interview on Friday, Mohsen Mahmoudi, head of Tehran's Islamic Development Coordination Council, had vowed it would be a "historic day for Islamic Iran and the revolution".

On the first day of the war on June 13, Israel killed Revolutionary Guards commander Hossein Salami.

He will be laid to rest after Saturday's ceremony, which will also honour at least 30 other top commanders.

Armed forces chief of staff General Mohammad Bagheri will be buried with his wife and journalist daughter who were killed alongside him in an Israeli strike.

Of the 60 people who are to be laid to rest after Saturday's ceremony, four are women and four are children.

Tehran is still coming to terms with the damage wrought by Israel's bombing campaign, the capital's first taste of war since the devastating 1980-88 conflict with Saddam Hussein's Iraq.

Israel bombed multiple residential neighbourhoods as it killed the senior figures being laid to rest on Saturday, many of them in their own homes.

Retaliatory drone and missile fire by Iran killed 28 people in Israel, according to official figures.