Former Trump legal spokesman Mark Corallo (left) and President Donald Trump's personal attorney Marc Kasowitz arrive to the National Press Club in Washington to read a statement to members of the media, Thursday, June 8, 2017.

The former spokesman for President Donald Trump's private legal team quit this summer because he believed a statement dictated by the president aboard Air Force One may have obstructed justice, an explosive new book claims.

That claim is reported in "Fire and Fury: Inside the Trump White House," by author Michael Wolff, which the White House says is full of "false and misleading" information. On Thursday, Trump's personal attorney sent a cease and desist letter to Wolff and his publisher, Henry Holt & Co., and demanded an apology for the content of the book.

The book is set to go on sale Tuesday, but excerpts have been made available to the public. NBC News has obtained a copy.



"Mark Corallo was instructed not to speak to the press, indeed not to even answer his phone," Wolff writes. "Later that week, Corallo, seeing no good outcome — and privately confiding that he believed the meeting on Air Force One represented a likely obstruction of justice — quit."



The statement the president reportedly dictated concerned the purpose of a June 2016 meeting between Trump's eldest son, Donald Trump Jr., senior advisor Jared Kushner, then-campaign chairman Paul Manafort and a Russian lawyer.



That initial explanation suggested the primary purpose of the meeting was to discuss Russian adoptions. That was later shown to be misleading, and Trump Jr. has said that the purpose of the meeting was to discuss potential dirt on political rival Hillary Clinton.



Advisors to the president told The Washington Post in July that the initial statement could raise questions about whether the president is attempting to hide something.

Corallo did not respond to a request for comment from CNBC.