President Donald Trump and Tesla CEO Elon Musk are trading barbs after the billionaire criticized the Republican spending bill making its way through Congress.

During an Oval Office meeting with the German chancellor, Trump said he was "very disappointed" in Musk, who has repeatedly railed against the bill.

"Elon knew the inner workings of this bill better than almost anybody sitting here," Trump said on Thursday.

He added, "All of a sudden, he had a problem, and he only developed the problem when he found out that we're going to have to cut the EV mandate."

Musk, who recently served as an adviser to the president, refuted those statements.

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"False, 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!" he said.

Musk went further, essentially saying he was responsible for Trump’s election victory.

"Without me, Trump would have lost the election, Dems would control the House and the Republicans would be 51-49 in the Senate," he said. "Such ingratitude."

Musk, who supported Trump’s candidacy with at least $250 million, has expressed frustration with the bill, which includes tax cuts and funding for other initiatives championed by the president. He said it adds to the federal deficit and undermines the work he did to trim government spending while leading the Department of Government Efficiency.

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