White House senior policy adviser Stephen Miller ripped into former White House chief strategist Steve Bannon and the credibility of the the now-released tell-all book, Fire and Fury: Inside the Trump White House, noting Bannon sounds like an “angry, vindictive person” in the book.

CNN host Jake Tapper pressed Miller on comments of Bannon featured in the book, including that Donald Trump Jr.’s meeting in June 2016 with a Russian lawyer was “ treasonous” and “unpatriotic.”

“Steve Bannon's eloquence in that derision notwithstanding, it's tragic and unfortunate that Steve would make these grotesque comments so out of touch with reality and obviously so vindictive and the whole White House staff is deeply disappointed in his comments, which were grotesque,” Miller told Tapper.

“And with respect to the Trump Tower meeting that he's talking about, he wasn't even there when any of this went down. So he's not a remotely credible source on any of it,” he added. “It reads like an angry, vindictive person spouting off to a highly discredible author. The book is best understood as a work of very poorly written fiction. And I also will say that the author is a garbage author of a garbage book.”

Content from the book, which was released on Friday, led Trump to denounce Bannon after it was revealed Bannon said unflattering things about Trump’s family once excerpts started to emerge.

Miller and Tapper also were at odds throughout the interview, as Miller criticized CNN on multiple occasions for their coverage of Trump.

“Your network's been going 24/7 with all the salacious coverage and I know it brings a lot of you guys a lot of joy to try to stick the knife in, but the reality is that page after page after page of the book is pure false,” Miller told Tapper. “I see sections of the book where events I participated in are described and I have firsthand knowledge as they're described they're completely and utterly fraudulent.”

Tapper then challenged Miller, saying no one at CNN was “sticking knives in anybody.”

At one point, Miller defended Trump calling himself a genius on Saturday, saying it happened to be a true statement. Tapper pushed back and said he was sure Trump was watching and was pleased by Miller’s response, causing Miller to accuse Tapper of being condescending for making the “snide remark.”

Eventually, Tapper cut the interview off.

“I think I've wasted enough of my viewers' time. Thank you, Stephen,” Tapper said concluding the interview.

Fire and Fury sent shockwaves through the political world this week as vivid excerpts were released, but the book’s integrity has been questioned by critics, who have pointed out several inconsistencies in Michael Wolff’s reporting.

For example, Maggie Haberman, White House correspondent for the New York Times, accused Wolff of getting "basic details wrong" about Trump's campaign and administration.

Henry Holt & Co., the book’s publisher, moved the release date up by four days after excerpts emerged, prompting Trump's legal team to submit a cease-and-desist letter to the publisher.