White House National Security Adviser Mike Waltz and other Trump administration staff have discussed government matters through personal Gmail accounts, the Washington Post reported on Tuesday, citing emails it obtained and three United States officials.

The media outlet claims that a senior Waltz aide used Gmail to talk with officials from other government agencies about "sensitive military positions and powerful weapons systems." Meanwhile, Waltz himself had "less sensitive, but ... exploitable information" on his Gmail account, including his schedule and different work documents, according to sources.

Gmail is not seen as suitable for government use as it is less secure than some other messaging apps, such as Signal. NSC spokesman Brian Hughes insisted he saw no evidence of what is being mentioned in WP's article, adding that "Waltz didn't and wouldn't send classified information on an open account."