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.

Waltz was at the center of the Signal chat controversy, in which a journalist was accidentally included in a discussion of sensitive military information.

A hacker breached TeleMessage, a company that sells a modified version of Signal to the US government. Mike Waltz was spotted using it last week.