Mr. Scaramucci had boasted about reporting directly to the president, not the chief of staff. But the decision to remove him came at Mr. Kelly’s request, the people said.
It was not clear whether Mr. Scaramucci, who is known informally as “The Mooch,” will remain at the White House in another position or will leave altogether. The White House had originally said that his official start date as a government employee was to be August 15, although he appeared to begin performing his duties immediately.
While Mr. Kelly’s objection was the decisive factor in Mr. Scaramucci’s departure, people close to the decision said that Mr. Trump had quickly soured on the wisecracking, Long Island-bred former hedge fund manager, and so had his family.
Ivanka Trump, the president’s daughter, and Jared Kushner, her husband, had pushed the president to hire Mr. Scaramucci, seeing him as a way to force out Mr. Priebus, the former national Republican committee chairman, and his allies in the West Wing.
In that, Mr. Scaramucci was successful. Mr. Spicer, a close ally of Mr. Priebus, resigned just hours after the news about Mr. Scaramucci’s hiring was made public. And shortly after Mr. Scaramucci called Mr. Priebus a “paranoid schizophrenic, a paranoiac,” — adding a more vulgar term to the beginning of the phrase — Mr. Priebus, too, offered his resignation.
Mr. Trump was initially pleased by Mr. Scaramucci’s harsh remarks, directed at Mr. Priebus and Steve Bannon, the chief White House strategist. But over the weekend, after speaking with his family and Mr. Kelly, the president began to see the brash actions of his subordinate as a political liability and potential embarrassment, according to two people familiar with his thinking.
Mr. Scaramucci’s swift departure is an early indication that Mr. Kelly intends to assert his authority over the operations of the White House, and that several of the big personalities there — including Mr. Kushner, Ms. Trump and Mr. Bannon — may be inclined to defer to him.
It also suggests that, at least for the moment, Mr. Kelly has the president’s support in that effort.
The president still values Mr. Scaramucci, according to people close Mr. Trump and his family, and is hoping to find another, less high profile, position for him in the White House — although it is uncertain if Mr. Scaramucci would be willing to accept a demotion.