Washington (CNN) President Donald Trump reprimanded his top military brass in a 2017 meeting at the Pentagon, calling them a "bunch of dopes and babies" and telling them "you're all losers," according to a forthcoming book by two Washington Post reporters.

The heated July 20, 2017 meeting has been previously reported -- including then-Secretary of State Rex Tillerson's response to fellow US officials, in which he said the President was a "f---ing moron ." However, "A Very Stable Genius" by Carol Leonnig and Philip Rucker reveals more extraordinary details about the meeting, including the President's barrage of insults against his top military leadership.

Tillerson, then-Secretary of Defense James Mattis and then-Director of the National Economic Council Gary Cohn hoped at the meeting to explain to the President about the importance of America's key alliances for national security. They were concerned that Trump's proposals were a threat to America's standing in the world, the Post reported.

Using lots of visual aids in an attempt to hold Trump's interest, the three men briefed the President on US deployments, bases and embassies around the world, and the value of trade agreements in boosting America's national security, the Post reported.

But during the briefing, at which the chairman of the Joint Chiefs of Staff and other top military leaders were present, Trump demanded an explanation as to why the US hasn't won in Afghanistan, calling it a "loser war," according to an excerpt adapted from the book and published in The Washington Post Friday. He frequently interrupted the briefing to object to US policies, like the Iran nuclear deal and the NATO alliance, the Post reported.

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