(CNN) President Donald Trump lashed out at acting chief of staff Mick Mulvaney during a Situation Room meeting with Democrats, including House Speaker Nancy Pelosi and Senate Minority Leader Chuck Schumer, earlier this month, a White House official said Sunday.

According to the official, Trump cut Mulvaney off toward the end of an unproductive meeting on re-opening the federal government, as Mulvaney was attempting to negotiate up from the $1.3 billion Democrats offered the White House.

"Stop, stop, just stop -- What are you doing? You're f---ing it all up, Mick," Trump said, according to the official who was in the room for the negotiations.

According to the source, there was "shockingly no reaction at all" in the room.

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