Omarosa Manigault-Newman, who first met Mr Trump when she appeared on The Apprentice, highlighted what she described as the President's deteriorating mental state in her new book, "Unhinged: An Insider's Account of the Trump White House".
"While watching the [Lester Holt] interview I realized that something real and serious was going on in Donald's brain. His mental decline could not be denied", Ms Manigault-Newman writes. On May 11, Trump told Holt: "When I decided [to fire Comey], I said to myself, I said, 'You know, this Russian Federation thing with Trump and Russian Federation is a made-up story'". They thought Trump was being Trump, off the cuff.
The former reality star claims Hope Hicks, then communications director, went over the briefing with Trump "a dozen times, hitting the key point that he had fired Comey based on the recommendation by the DOJ, which the vice president and other surrogates had been reinforcing for days".
Omarosa was beside herself when the president contradicted the White House party line that Federal Bureau of Investigation head James Comey was sacked based on the recommendation by the Department of Justice.
She adds: "Throughout this erratic and contradictory interview, I kept thinking, 'Oh no! Oh no! This is bad!'"
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The former "Apprentice" contestant drew press attention past year after she brought her 39-person bridal party inside the White House for an "extended" photo shoot in the Rose Garden.
As a result, she started writing a book titled Unhinged: An Insider's Account of the Trump White House, supposedly exposing Donald Trump.
She also told house guest Ross Matthews on the show that she didn't think America was in good hands. She was reportedly banned from posting any of the photos online by White House officials citing security and ethical concerns.
Now she is telling that story thanks to a seven-figure deal with Gallery Books, which is hyping up the book with lots of dramatic adjectives. When asked for reassurance about the state of the Trump White House, Omarosa replied: "It's gonna not be okay".
In December of a year ago, Omarosa was sacked from her communications director for the Office of Public Liaison position.
"I don't see it as a conflict of interest", she said.