In an eye-watering exchange with a New Yorker reporter late Wednesday, Scaramucci ranted about chief of staff Reince Priebus and chief White House strategist Steve Bannon.
"Reince is a f****** paranoid schizophrenic, a paranoiac," Scaramucci was quoted as saying in an expletive-filled tirade in which he accused the chief of staff of damaging information leaks.
"They're trying to resist me, but it's not going to work," he said, adding that Priebus would soon resign and using language that American television networks refused to repeat.
Turning his sights on Trump's chief strategist, Scaramucci made it very clear he believes Bannon is working in the White House to serve his own interests, using particularly offensive language.
"I'm not Steve Bannon, I'm not trying to suck my own c**k," he said.
"I'm not trying to build my own brand off the f****** strength of the president. I'm here to serve the country."
Scaramucci, a millionaire New York financier, has arrived at the White House vowing to serve Trump's interest and right a badly faltering administration.
But the revelations are likely to draw questions about whether his tenure at the White House will be a long one.
Scaramucci did not apologize for the tirade, but said he would try to clean up his language in the future.
"I sometimes use colorful language. I will refrain in this arena but not give up the passionate fight for @realDonaldTrump's agenda," he tweeted.
White House spokeswoman Sarah Sanders said Scaramucci "used some colorful language - I don't think he will again."
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