WASHINGTON — An escalating feud between President Trump and Elon Musk June 5 included threats to cancel SpaceX contracts and decommission spacecraft, although those words have yet to become actions.

In a heated exchange largely carried out on social media, Musk’s criticism of a budget reconciliation bill backed by Trump turned into full-fledged attacks on each other, less than a week after Musk ended his formal role in the administration as a “special government employee” overseeing the White House’s Department of Government Efficiency.

That exchange included a threat by Trump to cancel government contracts with Musk’s companies, such as SpaceX. “The easiest way to save money in our Budget, Billions and Billions of Dollars, is to terminate Elon’s Governmental Subsidies and Contracts,” Trump posted on his social media platform, Truth Social.

While the comment did not specifically mention SpaceX, Musk appeared to interpret it as a threat to SpaceX. “In light of the President’s statement about cancellation of my government contracts, @SpaceX will begin decommissioning its Dragon spacecraft immediately,” he posted on his social media platform, X, about 90 minutes later. He didn’t elaborate on what would be involved in “decommissioning” Dragon.

The back-and-forth between Musk and Trump raised fears that the White House might cut SpaceX off from its extensive work with NASA and the Defense Department, to the detriment of both the government and the company. It comes just months after many in the space industry worried that the then-close relationship between Musk and Trump might give SpaceX an unfair advantage.

Any loss of federal contracts would have a significant effect on SpaceX. Musk, in a rare glimpse into SpaceX finances, said June 3 that SpaceX is projecting $15.5 billion in revenue in 2025, of which $1.1 billion would come from NASA contracts. He did not disclose the amount coming from defense work, which would include launches as well as Starlink services and development of a reconnaissance satellite constellation for the National Reconnaissance Office.

The effects on the government from canceling those contracts, though, could be far greater. Both NASA and the Defense Department rely heavily on SpaceX for launch services as competing vehicles from other companies have been slow to enter service. SpaceX has the only operational vehicle, other than Russia’s Soyuz, to get crews to and from the International Space Station, and is a key cargo supplier. SpaceX also has a NASA contract to develop the U.S. Deorbit Vehicle, the spacecraft that will ensure a safe reentry of the station at the end of its life.

One industry source, speaking on background, dismissed the exchanges as “bluster” that neither Musk nor Trump would actually implement, noting the reliance the federal government has on SpaceX and SpaceX’s desire to retain government revenue.

Indeed, Musk, about five hours after making the threat to decommission Dragon, walked it back. “Good advice,” he wrote in a post, responding to a pseudonymous user who asked Musk to “cool off and take a step back for a couple days” from the debate. “Ok, we won’t decommission Dragon.”

NASA stood on the sidelines during the Trump-Musk exchanges. “NASA will continue to execute upon the President’s vision for the future of space. We will continue to work with our industry partners to ensure the President’s objectives in space are met,” said NASA press secretary Bethany Stevens.

The dispute between Musk and Trump overshadowed comments made by Trump earlier in the day about his decision announced May 31 to withdraw the nomination of Jared Isaacman to be NASA administrator.

Musk “wanted, and rightfully, recommended somebody that I guess he knew very well — I’m sure he respected him — to run NASA, and I didn’t think it was appropriate,” Trump said in a media availability with German Chancellor Friedrich Merz. Trump said that Isaacman was a Democrat, although Isaacman has donated to both Republican and Democratic candidates and organizations over the year.

“We won. We get certain privileges and one of the privileges is we don’t have to appoint a Democrat,” Trump said.

“NASA is very important. We have great people. Gen. Caine is going to be picking somebody. We’ll be checking him out,” he said, a reference to Gen. Dan Caine, chairman of the Joint Chiefs of Staff. It’s unclear why Trump asked Caine, an Air Force general with no space background, to select the head of the nation’s civil space agency.