Trump ousts Waltz as national security adviser and nominates him for UN post17 hours ago Share Save Bernd Debusmann Jr BBC News, at the White House Ali Abbas Ahmadi BBC News Share SaveMurmurs, a Trump post and a surprise - How Waltz's removal unfoldedUS President Donald Trump has removed Mike Waltz from his post as national security adviser, and will nominate him as ambassador to the United Nations. "From his time in uniform on the battlefield, in Congress and, as my National Security Advisor, Mike Waltz has worked hard to put our Nation's Interests first," Trump wrote in a post on Truth Social. "I'm deeply honoured to continue my service to President Trump and our great nation," he wrote. Minnesota Governor and former Democratic vice-presidential candidate Tim Walz made light of the national security adviser's exit on Thursday. He posted on X: "Mike Waltz has left the chat."