The White House has issued a formal threat to former national security adviser John Bolton to keep him from publishing his upcoming book, saying it contains significant amounts of classified information, including some that was considered "TOP SECRET".
President Donald Trump has launched a twitter attack on his former adviser for writing a "nasty and untrue book", saying he was fired "because frankly, if I listened to him we would be in World War Six by now".
It comes as Senate majority leader, Mitch McConnell, signalled he may not have the votes to block the Democrats' efforts to call witnesses, including Bolton, in the president's impeachment trial.
RNZ's correspondent in Washington is Simon Marks.
