(CNN) — The White House has issued a formal threat to former national security adviser John Bolton to keep him from publishing his book, “The Room Where It Happened: A White House Memoir,” sources familiar with the matter tell CNN.
The White House had no comment. Neither Bolton nor a spokesman for the publisher, Simon & Schuster, responded to a request for comment.
The letter comes in the midst of President Donald Trump attacking Bolton on Twitter, and Bolton’s lawyer accusing the White House of corrupting the vetting process for Bolton’s book by sharing the contents of the book with those outside the National Security Council’s Records Management Division.
Trump’s tweets attacking Bolton Wednesday morning suggested he knew the contents of the manuscript.
Reports from The New York Times suggest that Bolton’s book details a time last August when the President directly linked $391 million in security aid to Ukraine with that country’s government launching investigations into former Vice President Joe Biden and his son Hunter.
The President has repeatedly made unfounded and false claims about Joe Biden relating to Ukraine.
The President’s defense attorneys in his Senate impeachment trial have criticized the House impeachment managers for not producing any first-hand witnesses alleging that any quid pro quo came from the president himself.
Bolton has said he would be willing to testify in the Senate trial if subpoenaed. Trump has suggested that he might attempt to assert executive privilege and block Bolton’s testimony, though legal experts say the President’s tweets describing his conversations with Bolton about Ukraine might undermine any such assertion.