Elon Musk and Treasury Secretary Scott Bessent got into a heated shouting match in earshot of President Trump and other officials in the White House last week during a dispute about the IRS, two witnesses and three sources briefed on the matter tell Axios.

• "It was two billionaire, middle-aged men thinking it was WWE in the hall of the West Wing," one witness said of the argument last Thursday. (Bessent's net worth is actually $520 million.)

Why it matters: The clash — with both men in each other's face — showed how much Musk's personality and style have rankled some senior administration officials since he began running roughshod through agencies with DOGE.

• The New York Times first reported Friday that Bessent and Musk had a disagreement over who would lead the IRS. But the chest-to-chest clash between the two men a day earlier has not been reported previously.

• "They were not physical in the Oval, but the president saw it, and then they carried it down the hall, and that's when they did it again," the first witness said.

• Said a second: "It was quite a scene. It was loud. And I mean, loud."

Zoom in: Asked about the shouting match, White House Press Secretary Karoline Leavitt referred to comments she made to the Times about how "it's no secret President Trump has put together a team of people who are incredibly passionate about the issues impacting our country."

• "Disagreements are a normal part of any healthy policy process," her statement said. "And ultimately everyone knows they serve at the pleasure of President Trump."

• Representatives for Musk and Bessent declined to comment.

Musk has had high-profile disputes with Secretary of State Marco Rubio, Transportation Secretary Sean Duffy and Trade Adviser Peter Navarro as well.

• "Everyone thinks DOGE is great, but Elon's antics are just a bit much," another administration official said.

The backstory: Musk and Bessent had a choppy start during the presidential transition. Musk lobbied hard for Howard Lutnick to get the Treasury post. But Trump went with Bessent instead, and picked Lutnick to lead the Commerce Department.

• Once Trump became president, Musk and Bessent clashed over Treasury hires.

• "It wasn't a fight about right or wrong. It was about control," another administration official familiar with the disagreement said.

The big picture: The roots of the tension between Musk and Bessent is partly rooted in their personalities.

• Musk is a move-fast-and-break-stuff iconoclastic business leader and social media celebrity. Bessent is a cerebral, reserved financial guru who's much more comfortable explaining markets than being in the news. Or in a dispute with Musk, whom Bessent has praised along with DOGE.

• "What surprises a lot of people is Scott is so mild mannered. But he has his limits and he can roar," a Bessent ally who was briefed on the argument said.

• "Scott can't stand" Musk. "That goes pretty deep and pretty far back. But he's acting like a grown-up about it."

The intrigue: The latest trouble between Musk and Bessent began brewing on April 16, when Trump named Gary Shapley — Musk's choice — as acting commissioner of the IRS. Bessent wanted Deputy Treasury Secretary Michael Faulkender in the position.

• Bessent lobbied Trump to install Faulkender and fumed that Musk was causing trouble by going behind his back.

• On Thursday, at a meeting in the White House, Bessent confronted Musk and, a source said, "the F bombs started to fly."

• Bessent criticized Musk for overpromising and under-delivering budget cuts with DOGE. Musk clapped back by calling Bessent a "Soros agent" and accusing him of having run "a failed hedge fund." (Trump has praised Bessent's financial acumen.)

The argument was so heated that an aide stepped in between the two men to separate them. It took place within earshot of Italian Prime Minister Giorgia Meloni, who was visiting Trump that day.

• Two sources who overheard the argument recalled that at one point Bessent yelled," F**k you," and Musk replied, "Say it louder."

• That night, Trump loyalist Laura Loomer got in on the action and began torching Bessent on X for allowing an unrelated "Trump hater" into Treasury for a financial literacy event.

• "Troubling," Musk said in a quote-post reply at 11:02 p.m.

• But on Friday, Bessent had the last word when the Times reported that Shapley was out and Faulkender was in.

What's next: There's little appetite by Musk or Bessent for a rapprochement, and White House insiders wonder who'll fire the next shot.

• "Scott won that round," one source said. "But I would not want a guy like Musk as an enemy."