WASHINGTON — Elon Musk criticized the centerpiece of President Donald Trump’s legislative agenda, a significant fracture in a partnership that was forged during last year’s campaign and was poised to reshape American politics and the federal government.

The billionaire entrepreneur, who supported Trump’s candidacy with at least $250 million and has worked for his administration as a senior adviser, said he was “disappointed” by what the president calls his “big beautiful bill.”

The legislation includes a mix of spending and tax cuts as well as enhanced immigration enforcement. While speaking to CBS, Musk described it as a “massive spending bill” that increases the federal deficit and “undermines the work” of his Department of Government Efficiency, known as DOGE.

“I think a bill can be big or it could be beautiful,” Musk said. “But I don’t know if it could be both.”

His CBS interview came out Tuesday night. Trump, speaking in the Oval Office on Wednesday, defended his agenda by talking about the delicate politics involved with negotiating the legislation.

“I’m not happy about certain aspects of it, but I’m thrilled by other aspects of it,” he said.

Trump also suggested that more changes could be made. “We’re going to see what happens,” he said. “It’s got a way to go.”

Republicans recently pushed the measure through the House and are debating it in the Senate.

Musk’s comments come as he steps back from his government work, rededicating himself to his companies like the electric automaker Tesla and rocket manufacturer SpaceX. He’s also said he’ll reduce his political spending, because “I think I’ve done enough.”

At times, he has seemed chastened by his experience working in government. Although he hoped that DOGE would generate $1 trillion in spending cuts, he’s fallen far short of that target.

“The federal bureaucracy situation is much worse than I realized,” he told The Washington Post. “I thought there were problems, but it sure is an uphill battle trying to improve things in D.C., to say the least.”

The White House is set to send proposed rescissions, a mechanism used to cancel authorized spending, to Capitol Hill to solidify some of DOGE’s cuts.

A spokesperson for the Office of Management and Budget said the package will include $1.1 billion from the Corporation of Public Broadcasting, which funds NPR and PBS, and $8.3 billion in foreign assistance.

Musk had been energized by the opportunity to reshape Washington. He wore campaign hats in the White House, held his own campaign rallies and talked about excessive spending as an existential crisis.

He tended to be effusive in lauding Trump. “The more I’ve gotten to know President Trump, the more I like the guy,” he said in February. “Frankly, I love him.”

Trump repaid the favor, describing Musk as “a truly great American.” When Tesla faced declining sales, he turned the White House driveway into a showroom to illustrate his support.

It’s unclear what, if any, impact that Musk’s comments about the bill would have on the legislative debate. During the transition period, he helped whip up opposition to a spending measure as the country stood on the brink of a government shutdown.

House Speaker Mike Johnson has asked senators to make as few changes to the legislation as possible, saying that House Republicans reached a “very delicate balance” that could be upended by major changes. The narrowly divided House will have to vote again on final passage once the Senate alters the bill.

But Musk’s criticism could embolden Republicans who want bigger spending cuts. Republican Utah Sen. Mike Lee reposted a Fox News story about Musk’s interview while also adding his own take on the measure, saying there was “still time to fix it.”

“The Senate version will be more aggressive,” Lee said. “It can, it must, and it will be. Or it won’t pass.”

Only two Republicans — Reps. Warren Davidson of Ohio and Thomas Massie of Kentucky — voted against the bill when the House took up the measure last week.

The Congressional Budget Office, in a preliminary estimate, said the tax provisions would increase federal deficits by $3.8 trillion over the decade, while the changes to Medicaid, food stamps and other services would cut spending by slightly over $1 trillion in the same period.

House Republican leaders say increased economic growth would allow the bill to be deficit neutral or reducing. The Committee for a Responsible Federal Budget estimates the bill would add $3 trillion to the debt, including interest, over the next decade.