Elon Musk has launched a blistering attack on President Donald Trump’s flagship tax and spending bill, calling it a “disgusting abomination” in a fiery post on X, signaling a growing rupture between the billionaire tech mogul and the former president.

The legislation—central to Trump’s second-term agenda—was passed by the House last month and is currently under Senate review. It proposes multi-trillion-dollar tax cuts, a substantial boost to defense spending, and raises the federal borrowing limit to $4 trillion. Economists warn it could swell the U.S. budget deficit to $2.5 trillion.

“Shame on those who voted for it,” Musk wrote Tuesday. “This outrageous, pork-filled bill massively increases the already gigantic budget deficit and burdens American citizens with crushingly unsustainable debt.”

Musk’s sharp rebuke comes just days after his departure from the Trump administration, where he led the controversial cost-cutting initiative known as Doge for 129 days. Trump had previously praised Musk’s tenure, saying he would “always be with us, helping all the way.” However, Musk’s latest remarks suggest an intensifying split between the two once-close allies.

Though Musk had previously labeled the bill “disappointing,” Tuesday marked his most forceful condemnation yet. He also issued a political warning: “In November next year, we fire all politicians who betrayed the American people.”

The bill has ignited infighting within the Republican Party. Senator Rand Paul has pledged to vote against it, criticizing the ballooning debt ceiling. “The GOP will own the debt once they vote for this,” Paul said. Trump fired back on social media, mocking Paul’s objections and calling him “unpopular in Kentucky” with “very little understanding of the bill.”

Despite Musk’s criticism, Senate Majority Leader John Thune insisted the party would move forward with the bill. House Speaker Mike Johnson, who played a key role in shepherding the legislation through the House, said he spoke with Musk for 20 minutes this week and tried to address his concerns, including those related to the phasing out of electric vehicle tax credits.

“It’s a very important first step,” Johnson said. “Elon is missing it. I deeply regret he’s made this mistake.”

Sources close to Musk say his frustration is also rooted in a failed push to have the Federal Aviation Administration adopt his company’s Starlink technology for national air traffic control—an initiative that was ultimately rejected over concerns about feasibility and conflicts of interest.

The sweeping spending package extends Trump-era tax cuts, directs billions toward defense and immigration enforcement, and slashes funding for agencies like USAID, NPR, and PBS. It also includes $9.4 billion in proposed cuts—sourced from recommendations made by Musk’s former Doge team—to appease fiscal conservatives.

Ironically, some Democrats welcomed Musk’s break from Trump. “Even Elon Musk, who’s been part of this whole effort and one of Trump’s biggest backers, is calling out how bad this bill is,” said Senate Minority Leader Chuck Schumer.

Musk, who donated over $250 million to Trump’s re-election campaign, has long aligned with Trump’s deregulatory, pro-business, and nationalist policies. His sudden turn against the administration’s signature legislation could have ripple effects throughout Republican ranks—especially among voters and lawmakers who have looked to Musk as a bellwether of conservative tech and business support.