Elon Musk publicly ripped into a top White House aide who fueled his falling out with President Donald Trump.

Tensions had already been building between Musk and Trump before the SpaceX chief left the White House. Things got ugly, however, after Sergio Gor, the director of the presidential personnel office, encouraged Trump to rescind his nomination for Jared Isaacman—Musk’s personal friend—to lead NASA.

Sergio Gor is a close ally to President Donald Trump's son Don Jr. Evelyn Hockstein/Reuters

“He’s a snake,” Musk wrote on his social media platform X late Wednesday in response to the Post’s report.

Elon Musk called Trump aide Sergio Gor a “snake” in response to a report that Gor has not yet been fully vetted, despite being in charge of vetting members of Trump’s team. Elon Musk X

According to the Post, Gor, 38, developed a grudge against Musk, 53, after the Tesla chief—who as head of the government cost-cutting task force DOGE was a de facto member of Trump’s Cabinet—“humiliated” him in front of other Cabinet members for not staffing the administration quickly enough.

“Sergio was upset about Elon dressing him down at the meeting and said he was going to ‘get him,’” a source told the paper.

At the time, Musk and Trump were still on friendly terms, but Gor was openly gleeful whenever Tesla stock plunged, according to the report. After Musk’s special government employee status expired, forcing him to leave the White House, Gor reportedly got his revenge on Musk by convincing Trump to pull Isaacman’s nomination just days before the Senate was scheduled to vote on the appointment.

Jared Isaacman said he didn't think his nomination to lead NASA was really pulled over his campaign donation history. Ken Cedeno/REUTERS

The administration blamed the move on Isaacman’s previous donations to Democrats, but the billionaire financial technology executive said he didn’t think that was the real reason, considering his donation history had long been in the public domain.

After the nomination was pulled, Musk—who poured more than $250 million into the president’s re-election campaign—began publicly trying to tank the president’s flagship “big beautiful” budget bill.

Surprisingly little is known about Gor, including his birthplace, according to the Post. He declined to tell the paper where he was born, except to say that it wasn’t Russia. It’s previously been reported that he was born in Malta, but an official there couldn’t confirm that information, the paper said.

Together with Donald Trump Jr., Gor co-founded a publishing company that published several of Trump’s books following the end of President Trump’s first term, according to the New York Times.

Sergio Gor walking on the South Lawn of the White House with Treasurty Secretary Scott Bessent on April 6, 2025. CHRIS KLEPONIS/Chris Kleponis/AFP via Getty Images

In a statement to the Daily Beast, White House press secretary Karoline Leavitt said, “Sergio Gor is a trusted adviser to President Trump and he has played a critical role in helping President Trump staff the most talented administration in history.”

Gor’s office is responsible for assessing candidates for about 4,000 political appointees, including handling security clearances and conflicts of interest. Gor, however, has yet to turn in Standard Form 86, the 100-page background investigation form required for a security clearance, according to the Post.

The form covers citizenship, employment history, relatives, foreign contacts and travel, financial activities, drug use, and more.

Despite three sources saying otherwise, a White House official claimed Gor had completed the SF-86 form and noted that he has an interim security clearance, which is given while background checks are completed.