National security adviser Mike Waltz is leaving his White House post, although soon after reports about his departure were published, President Trump announced he plans to nominate him to be ambassador to the United Nations.

Mike Waltz, who played a central role in the Signal-gate, is now out as Trump's National Security Advisor, but why did he decide to resign?

President Donald Trump is replacing his National Security Adviser, Mike Waltz, and nominating him to be Ambassador to the United Nations, he announced Thursday, marking the first major personnel shake-up of Trump’s second term.