National Security Advisor Mike Waltz is expected to leave his post in the Trump administration on the heels of controversy over the creation of a Signal messaging app group that was used to discuss U.

US President Donald Trump's national security adviser Mike Waltz has officially resigned from his role in the White House, after his Signal group chat was exposed in March

Waltz was told this week that he is being forced out, but has not been formally fired yet, several media outlets reported, citing administration sources.