US President Donald Trump suggested on Tuesday that his department of government efficiency (DOGE) should take a look at the subsidies Tesla CEO Elon Musk's companies have received to save the federal government “big” money.

Trump's comments come after billionaire Musk renewed his criticism on Monday of Trump's sweeping tax cut and spending bill, vowing to unseat lawmakers who backed it after campaigning on limiting government spending.

“Elon may get more subsidy than any human being in history, by far, and without subsidies Elon would probably have to close up shop and head back home to South Africa. No more rocket launches, satellites or electric car production and our country would save a fortune. Perhaps we should have DOGE take a good, hard, look at this? Big money to be saved,” Trump said in a post on Truth Social.

In response to Trump's post, Musk, on his social media platform X, said: “I am literally saying cut it all. Now.”

After weeks of relative silence after a feud with Trump over the legislation, Musk rejoined the debate on Saturday as the Senate took up the package, calling it “utterly insane and destructive” in a post on X.

On Monday he ramped up his criticism, saying lawmakers who had campaigned on cutting spending but backed the bill “should hang their heads in shame”.

“They will lose their primary next year if it is the last thing I do on this Earth,” Musk said.

The Tesla and SpaceX CEO called again for a new political party, saying the bill's massive spending indicated “we live in a one-party country, the porky pig party”.  

“Time for a new political party that actually cares about the people,” he wrote.

Musk's criticism of the bill has caused a rift in his relationship with Trump, marking a dramatic shift after the tech billionaire spent nearly $300m (R5.3bn) on Trump's re-election campaign and led the administration's controversial DOGE, a federal cost-cutting initiative.

Musk, the world's richest man, has argued the legislation would greatly increase the national debt and erase the savings he said he  achieved through DOGE.

It remains unclear how much sway Musk has over Congress or what effect his opinions might have on the bill's passage.  Republicans have expressed concern that his on-again, off-again feud with Trump could hurt their chances to protect their majority in the 2026 midterm congressional elections.

The rift has also led to volatility for Tesla, with shares of the company seeing wild price swings that erased approximately $150bn (R2.6-trillion) of its market value, though it has since recovered.