"It's just nasty stuff," Trump said of the scathing details in Woodward's tome, which the president suggested might be from "disgruntled employees or just made up" by the reporter.

"I probably would have preferred to speak with him, but maybe not. I think it probably wouldn't have made a difference in the book. He wanted to write the book a certain way," the president said.

"He's had a lot of of credibility problems," Trump told The Daily Caller in an an interview about Woodward's book, "Fear: Trump in the White House."

President Donald Trump on Tuesday called a new book on his White House by famed investigative journalist Bob Woodward "just another bad book" and "nasty stuff."

The forthcoming expose says that Trump referred to Attorney General Jeff Sessions as a "traitor," and "mentally retarded," while himself being called an "idiot" by White House chief of staff John Kelly in discussions with associates.

The Washington Post, published an article detailing those and other highlights of the book, which include claims that Trump administration officials snatched documents off of the president's desk to avoid having him sign them, that Trump compared his first chief of staff, Reince Priebus, to "a little rat," and called for the assassination of Syria's leader.

The article said Woodward's book "reveals a 'nervous breakdown' of Trump's presidency."

In a late-night Tuesday Twitter post, Trump pushed back against the reporting about the alleged comments on Sessions.

Donald Trump tweet: The already discredited Woodward book, so many lies and phony sources, has me calling Jeff Sessions "mentally retarded" and "a dumb southerner." I said NEITHER, never used those terms on anyone, including Jeff, and being a southerner is a GREAT thing. He made this up to divide!

Woodward, who first gained famed for his reporting with Washington Post colleague Carl Bernstein on the Watergate scandal that ended the presidency of Richard Nixon, told Trump in a call last month that he had repeatedly sought an interview with Trump but received no response from the president's aides. Trump told Woodward he would have "loved" to speak to him for the book.

White House Press Secretary Sarah Huckabee Sanders, in a statement, said, "This book is nothing more than fabricated stories, many by former disgruntled employees, told to make the President look bad."

Kelly issued a statement of his own denying that "I ever called the President an idiot."

Kelly is quoted in the book as saying of Trump, "It's pointless to try to convince him of anything. He's gone off the rails. We're in Crazytown. I don't even know why any of us are here. This is the worst job I've ever had."

John Dowd, Trump's former lawyer, on Tuesday denied to Axios that he had believed that the president was a "f---ing liar," as Woodward's book claims.

Defense Secretary Jim Mattis also denied saying the quotes attributed to him, referring to them as "a product of someone's rich imagination."

In the highlights published by the Post, Mattis is described as frustrated with the president, likening his understanding to that of a "fifth- or sixth-grader."

Woodward told The Post on Tuesday that he stood by his reporting.

@costareports: Woodward statement: "I stand by my reporting."

Both Kelly's denial and Sanders' broadside against the Woodward book were released with a list of more than 50 "accomplishments" that the Trump administration says it has achieved since early 2017.

The final item on that list reads "We have begun BUILDING THE WALL. Republicans want STRONG BORDERS and NO CRIME. Democrats want OPEN BORDERS which equals MASSIVE CRIME."