The breakup between the president of the United States and the world’s richest man is unfurling much like their relationship started — rapidly, intensely and very publicly.

Then, he threatened to cut Musk’s government contracts as their fractured alliance rapidly escalated into a public feud.

Hours after Trump lamented his breakup with Musk and Musk responded on social media, Trump escalated the feud by threatening to use the US government to hurt Musk’s bottom line.

“The easiest way to save money in our Budget, Billions and Billions of Dollars, is to terminate Elon’s Governmental Subsidies and Contracts,” Trump wrote on his social media network.

“I was always surprised that Biden didn’t do it!”

In the Oval Office, Trump said he was “very disappointed” with Musk after the billionaire former backer lambasted the president’s signature bill of tax cuts and spending plans.

Trump suggested Musk, who left the government last month after spearheading the tumultuous Department of Government Efficiency, misses being in the White House and has “Trump derangement syndrome”.

“Look, Elon and I had a great relationship. I don’t know if we will anymore,” Trump said.

He said that he had helped Musk a lot and brushed aside the billionaire’s efforts to get him elected last year, claiming that he would have won closely contested Pennsylvania even without Musk’s help, which included spending at least $US250 million ($384 million) supporting his campaign last year.

The Republican president’s comments came as Musk has continued a storm of social media posts attacking Trump’s “Big Beautiful Bill” and warning it will increase the federal deficit. Musk has called Trump’s big tax break bill a “disgusting abomination”.

As Trump spoke to reporters at the White House on Thursday, Musk was watching.

“False,” he fired back on his social media platform as the president continued speaking.

“This bill was never shown to me even once and was passed in the dead of night so fast that almost no one in Congress could even read it!”

Trump said Musk, the CEO and founder of Tesla, “only developed a problem” with the bill because it rolls back tax credits for electric vehicles.

“Whatever,” Musk snapped back in a post on X responding to a video clip of the moment.

He went on and said Trump could keep the cuts but should “ditch the MOUNTAIN of DISGUSTING PORK in the bill”.

The bill would unleash trillions of dollars in tax cuts and slash spending but also spike deficits by $US2.4 trillion ($3.7 trillion) over a decade and leave some 10.9 million more people without health insurance, according to an analysis by the Congressional Budget Office, which for decades has served as the official scorekeeper of legislation in Congress.

Trump says it might be better to let Ukraine and Russia ‘fight for a while’

Also while meeting with Merz, Trump said it might be better to let Ukraine and Russia “fight for a while” before pulling them apart and pursuing peace.

likened the war in Ukraine — which Russia invaded in early 2022 — to a fight between two young children who hated each other.

“Sometimes you’re better off letting them a fight for a while and then pulling them apart,” Trump said. He added that he had relayed that analogy to Russian President Vladimir Putin in their phone conversation on Wednesday.

Asked about Trump’s comments as the two leaders sat next to each other, Merz stressed that both he and Trump agreed “on this war and how terrible this war is going on”, pointing to the US president as the “key person in the world” who would be able to stop the bloodshed.

But Merz also emphasised that Germany “was on the side of Ukraine” and that Kyiv was only attacking military targets, not Russian civilians.

“We are trying to get them stronger,” Merz said of Ukraine.

Thursday’s meeting marked the first time that the two leaders sat down in person. After exchanging pleasantries — Merz gave Trump a gold-framed birth certificate of the USS president’s grandfather Friedrich Trump, who immigrated from Germany — the two leaders were to discuss issues such as Ukraine, trade and NATO spending.