Trump's national security adviser Mike Waltz steps down, US media report

Waltz created the group chat on the Signal messaging app to which a journalist from The Atlantic was inadvertently added where officials shared plans about imminent military strikes on Houthi targets in Yemen.

US National Security Adviser Mike Waltz has stepped down from his post, US media are reporting.He is the first senior member of the Trump administration to leave. Waltz's decision came as US President Donald Trump marks his first 100 days in office.Waltz came under fire as it became known he created the group chat on the Signal messaging app — to which a journalist from The Atlantic was inadvertently added — where top US officials shared plans about imminent military strikes on Houthi targets in Yemen.The White House downplayed the security risks, saying no classified material had been shared in the chat.Our journalists are working on this story and will update it as soon as more information becomes available.