Donald Trump and Elon Musk reignited their bitter feud on Tuesday, with the US president threatening to deport the tech tycoon and strip federal funds from his businesses for criticising Trump’s flagship spending bill.

The world’s richest person was Trump’s biggest political donor in the 2024 election, and became his inseparable ally during his first months back in the White House as head of the Department of Government Efficiency (DOGE).

But the Space X and Tesla boss is now threatening to turn his riches against Trump, mulling a rival political party to challenge Republican lawmakers who vote for the president’s “One Big Beautiful Bill”.

Trump, 79, reacted vengefully today as he headed to the opening of a new migrant detention centre in Florida dubbed “Alligator Alcatraz”.

“We’ll have to take a look,” he told reporters when asked if he would consider deporting Musk, who has held US citizenship since 2002.

Trump also signalled that he could take aim at the huge contracts and subsidies that Musk’s Space X rocket and Starlink satellite internet businesses receive from the US government.

“We might have to put DOGE on Elon. You know what DOGE is? DOGE is the monster that might have to go back and eat Elon,” Trump said.

Trump added later in Florida: “I don’t think he should be playing that game with me.”

‘Head back home’

In reply to a post on his X social network featuring Trump’s deportation comments, Musk said on Tuesday: “So tempting to escalate this. So, so tempting. But I will refrain for now.”

Shares of Tesla sank around five per cent after Trump’s threats.

Trump had made similar comments on Monday, saying Musk was attacking the bill because he was annoyed that it had dropped measures to support the electric vehicles (EV) industry.

“Without subsidies, Elon would probably have to close up shop and head back home to South Africa,” Trump said on his Truth Social network.

The tycoon and the president shared a brief but intense bromance after Trump’s return to power in January.

Wearing MAGA baseball hats, Musk was an almost constant presence at Trump’s side. Trump returned the favour by promoting Tesla electric vehicles when protesters targeted them for Musk’s cost-cutting drive at DOGE.

But they had a huge public blow-up in May as Musk criticised the spending bill and then left the government.

‘Don’t bankrupt America’

Musk had kept a low profile in recent weeks but returned to the fray as the bill began its difficult path through Congress.

He has since posted a steady stream of posts against the bill on the X social network that he owns.

The billionaire’s criticisms centre on claims that the bill would increase the US deficit. He also accuses Republicans of abandoning efforts to place the US at the front of the EV and clean energy revolution.

“All I’m asking is that we don’t bankrupt America,” he said on social media today, accusing Republicans of supporting “debt slavery”.

More worrying perhaps for Trump is the way that Musk is seeking to target vulnerable Republican lawmakers ahead of the 2026 US midterm elections.

Musk has said he will set up his own political movement called the “America Party” if Trump’s bill passes.

And he has pledged to fund challengers against lawmakers who campaigned on reduced federal spending only to vote for the bill.

“Vox Populi, Vox Dei (the voice of the people is the voice of God) 80pc voted for a new party,” he said after launching a poll on the idea on X.