U.S. Defense Secretary Pete Hegseth gestures as he meets with El Salvador Defense Minister Rene Merino Monroy at the Pentagon in Washington, D.C., U.S., April 16, 2025. REUTERS/Ken Cedeno

President Donald Trump was reportedly furious upon learning that Defense Secretary Pete Hegseth had invited tech billionaire Elon Musk — a recent Trump ally with whom he had a public falling-out this week — to a Pentagon briefing.

The Atlantic reported Thursday that the meeting, which took place in March, was later described by Trump and Hegseth as a session focused on Musk's role in the Department of Government Efficiency (DOGE).

Trump publicly dismissed the report about Musk having attended the Pentagon briefing as "fake news" at the time. But privately, he was angered by Musk's inclusion.

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According to the report, upon learning of the briefing the night before it was set to occur, the president contacted Hegseth to express his disapproval.

He described the invitation as “a bad look” for the administration. The following day, during an in-person conversation, Trump reportedly reiterated his dissatisfaction, stating, “This is crazy and stupid,” and questioning, “Why would we even do this?”

The report further claims that the incident marked a significant shift in Hegseth's tenure as Defense Secretary and his relationship with Trump.

The briefing, held in the Pentagon's elite conference room known as "the Tank," where top officers meet with the president, was perceived as a breach of protocol and added to the controversy, per the report.

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Meanwhile, the once-amicable relationship between Trump and Musk has deteriorated into a highly publicized feud. The conflict ignited when the Tesla CEO criticized Trump's major legislative initiative, the "One Big Beautiful Bill," labeling it a "disgusting abomination" on his social media platform, X.

In retaliation, Trump expressed his disappointment and threatened to revoke government contracts with Musk's companies, including Tesla and SpaceX, which receive substantial federal subsidies.

The situation escalated further when Musk alleged in another X post Thursday that Trump appears in government documents related to convicted sex trafficker Jeffrey Epstein, suggesting that this was the reason certain documents have not been made public.

AlterNet reached out to the White House for comment.

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