Lawyers for the author and publisher of an explosive new book on President Donald Trump issued a letter Monday to the presidents attorney, refusing to cease publication.

Fire and Fury author Michael Wolff gained enormous national attention last week after it came to light that his book included startling comments from former White House chief strategist Steve Bannon . In an interview with Wolff, Bannon said that a June 2016 meeting in New Yorks Trump Tower between Donald Trump Jr. and Kremlin-linked Russian operatives was treasonous. Bannon also implied the elder Trump was aware of the appointment at the time , something the president has denied . Bannon has since backpedaled on his interview after losing the admiration of his supporters .

Trumps attorney, Charlie Harder, issued cease-and-desist letters last week to Bannon, Wolff and publisher Henry Holt . The letters only spurred the early release of Fire and Fury, which sold out rapidly once available in bookstores.

Holt and Wolffs attorney, Elizabeth McNamara, replied to Trumps attorney in a letter Monday that denounced the presidents attempt to silence critics with an unsubstantiated threat of a libel suit.

My clients do not intend to cease publication, no such retraction will occur, and no apology is warranted, McNamara wrote in a letter obtained by HuffPost.

Though your letter provides a basic summary of New York libel law, tellingly, it stops short of identifying a single statement in the book that is factually false or defamatory, the letter continued. Instead, the letter seems designed to silence legitimate criticism.

Trumps cease-and-desist letter to Wolff and Holt mentioned the obligations for the publisher and author to retain any documents regarding the book and the 200 interviews Wolff conducted in his research. McNamaras letter issues a similar warning to the presidents lawyer.

We must remind you that President Trump, in his personal and governmental capacity, must comply with the same legal obligations regarding himself, his family members, their businesses, the Trump campaign and his administration, and must ensure all appropriate measure to preserve such documents are in place, her letter read.

McNamara continued by saying that in the event of a lawsuit, such documents would prove particularly relevant to our defense.

Fire and Fury contains several troubling and incendiary claims that have put the Trump administration on the defense. In addition to Bannons Russia comments, Wolff reported on doubts surrounding Trumps leadership abilities and mental capacity.

Trump, for his part, spent days on Twitter denouncing Wolff as the author of a phony book and defending himself as a very stable genius.