US national security adviser Mike Waltz is reportedly leaving his post.
Mr Waltz faced scrutiny for creating a chat on messaging app Signal in which defence secretary Pete Hegseth and other officials discussed strikes on Yemen’s Iran-backed Houthis.
It came to light after Mr Waltz accidentally added a US journalist to the group.
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Signal is regarded as highly secure but state-sponsored hackers are believed to have the capability to intercept messages.
A transcript showed Mr Hegseth provided timings of aircraft launches and when bombs would drop.
Mr Waltz said he took “full responsibility” but insisted he didn’t know how Jeffrey Goldberg ended up on the chat and maintained he didn’t know the journalist.
The White House said no classified information was shared and publicly stood by Mr Waltz.
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‘Nobody was texting war plans’ – Hegseth
However, Reuters and AP news agencies cited anonymous sources on Thursday and said he would now leave after less than five months in the job.
His deputy, Alex Wong, is also said to be going.
Mr Waltz is a highly decorated special forces veteran and the first Green Beret to serve in Congress.
The 51-year-old was also Donald Trump‘s fifth permanent national security adviser after he went through four during his first term.
His departure is the first major change in the president’s top team this time round – and comes shortly after he marked 100 days in office.
It’s so far unclear who will take over.
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The ‘Signalgate’ episode, which came to light in March, was reportedly not the only breach of security protocol involving senior officials.
The defence secretary reportedly had his wife, brother and lawyer on another group chat about the Yemen strikes.
President Trump has publicly backed Mr Hegseth, saying today said he was doing a “fantastic job”, but some experts believe his position is also at risk.
