Trump to Withdraw Musk’s Ally as Nominee for Top NASA Job

President Trump on Saturday said that he planned to withdraw his nomination of Jared Isaacman, a billionaire entrepreneur and close associate of Elon Musk’s, to be the next NASA administrator, days before Mr. Isaacman’s expected confirmation to the role by the Senate.

Mr. Trump in recent days told associates he intended to yank Mr. Isaacman’s nomination after being told that he had donated to prominent Democrats, according to three people with knowledge of the deliberations who were not authorized to discuss them publicly. Mr. Trump said on social media on Saturday that he had conducted a “thorough review of prior associations” before deciding to withdraw the nomination.

Mr. Trump added that he would “soon announce a new Nominee who will be Mission aligned, and put America First in Space.”

The U-turn was the latest example of how Mr. Trump uses loyalty as a key criterion for top administration roles, and came at a fraught moment for the space agency. NASA has so far been spared the deep cuts that have hit the National Science Foundation, the National Institutes of Health and other federal research agencies. But the Trump administration’s budget proposal for 2026 seeks to slice the space agency’s budget by one-quarter, lay off thousands of employees and end financing for a slew of current and future missions.

The Trump administration also wants to overhaul NASA’s human spaceflight program, ending the Space Launch System rocket and Orion crew capsule initiatives after the Artemis III mission that is to land astronauts on the moon in 2027 and adding money to send astronauts to Mars in the coming years, something that had been a priority for Mr. Musk.

People inside and outside NASA had hoped that Mr. Isaacman’s arrival as administrator would help provide stability and a clearer direction for the agency, which has been operating under an acting administrator since the beginning of Mr. Trump’s term.

Mr. Isaacman, who declined to comment when reached by phone on Saturday, was informed of the decision on Friday, which was also Mr. Musk’s last day in the White House as a special government employee.

Even if Mr. Trump announces a new choice relatively soon, the agency will now face several more months before a top leader is in place.

Mr. Trump told associates he had learned from allies that Mr. Isaacman had donated to Democrats, including Senator Mark Kelly of Arizona and former Senator Bob Casey of Pennsylvania, as well as the California Democratic Party, during the past two campaign cycles, the people with knowledge of the deliberations said.

Mr. Trump told advisers he was surprised he had not been told about those donations previously, two people briefed on the matter said, neither of whom was authorized to discuss the matter. Sergio Gor, the director of the Presidential Personnel Office who has clashed with Mr. Musk over nominees, supported Mr. Trump’s moving to withdraw the nomination, two other people briefed on the matter said.

An aide to Mr. Musk did not respond to a message seeking comment.

Installing Mr. Isaacman, 42, at NASA was one of the biggest benefits that Mr. Musk had pulled off for himself. The space agency previously had a $25 billion budget and is crucial to Mr. Musk’s rocket business, SpaceX. Mr. Isaacman, a pilot who has privately flown to space twice with SpaceX, ingratiated himself with the president by giving $2 million to Mr. Trump’s inaugural committee.

It would be an extraordinary move to withdraw the nomination, given that Mr. Isaacman had already been approved by the Senate Commerce, Science and Transportation Committee with a 19-to-9 vote. He was scheduled to be confirmed by the full Senate next week. It will also be a test case for how much of Mr. Musk’s influence remains in a White House where he is no longer physically working as an adviser.

Mr. Trump told Mr. Musk on Friday that he intended to pull back Mr. Isaacman’s nomination, according to a person with knowledge of their conversation.

Mr. Isaacman is the chief executive of the payment processing company Shift4 Payments, and Mr. Trump lauded him when he announced his selection in December.

“Jared will drive NASA’s mission of discovery and inspiration, paving the way for groundbreaking achievements in Space science, technology, and exploration,” Mr. Trump posted on Truth Social at the time.

Mr. Musk lobbied for Mr. Isaacman’s selection directly with Mr. Trump, according to a person with knowledge of the discussions. Mr. Trump is said to have deferred to Mr. Musk on the choice, contending that he was knowledgeable about space because of his success with SpaceX, the person said.

No major speed bumps came up during Mr. Isaacman’s nomination hearing in April before the commerce committee. Senator Ted Cruz, the Texas Republican who leads the committee, pushed Mr. Isaacman to acknowledge the goals Congress had set out for NASA, in particular the Artemis program to send astronauts back to the moon in the coming years.

Senator Edward Markey, Democrat of Massachusetts, noted the close ties between Mr. Isaacman and his companies and Mr. Musk. He asked several times whether Mr. Musk had been present at Mar-a-Lago in Florida when Mr. Trump offered Mr. Isaacman the NASA position. Mr. Isaacman did not directly reply. He would only say, repeatedly, that his interview had been with Mr. Trump.

Mr. Cruz and the other Republicans on the committee voted to advance the nomination, as did four Democrats, including Senator Maria Cantwell of Washington, the top Democrat on the panel.

On Saturday, allies of Mr. Musk’s began publicly defending Mr. Isaacman, trying to change the president’s mind about withdrawing the nomination.

His defenders included Laura Loomer, the far-right activist who has often been critical of other Trump nominees with histories of supporting Democrats. She posted a lengthy message on X casting Mr. Isaacman’s impending removal as a “deep state” plot to undermine the president.

Some Republican lawmakers also rallied to Mr. Isaacman’s defense on Saturday. Senator Tim Sheehy of Montana, an ally of Mr. Trump’s who serves on the committee that approved Mr. Isaacman’s nomination, posted on X that “astronaut and successful businessman @RookIsaacman was a strong choice by President Trump to lead NASA.”

“I was proud to introduce Jared at his hearing,” Mr. Sheehy added, “and strongly oppose efforts to derail his nomination.”