The White House has told former security adviser John Bolton that the draft manuscript of his book still contains classified information, his attorney Charles Cooper told US media on Wednesday.
According to Cooper, White House deputy counsel John Eisenberg sent him a letter saying that "the unauthorised disclosure of classified information could be exploited by a foreign power, thereby causing significant harm to the national security of the United States".
The White House is to give Bolton a redacted copy of the manuscript by 19 June, just four days before the ex-adviser plans to publish his book.
Excerpts from Bolton's book, which were leaked during the failed impeachment efforts against Trump, were deemed as a hint that the president was trying to put pressure on Kiev into investigating potential corruption dealings of former vice president Joe Biden and his son, Hunter, in Ukraine, The New York Times reported in late January.
On 10 September, President Trump said he asked Bolton to resign following failed negotiations between the US and the Taliban. Trump wrote on Twitter at the time that he "disagreed strongly with many of his suggestions, as did others in the administration".
Bolton was considered one of the most hawkish officials in the Trump administration, as he had urged the president to deepen US involvement in Venezuela's affairs and strengthen pressure on Iran and North Korea. Trump once said that if he had listened to Bolton's hawkish foreign policy advice, the US "would be in World War Six by now".