US national security adviser Mike Waltz is reportedly leaving his post.
Mr Waltz faced scrutiny after it emerged he created a group chat on messaging app Signal in which defence secretary Pete Hegseth and other US officials discussed strikes on Yemen’s Iran-backed Houthis.
It came to light after Mr Waltz accidentally added a US journalist to the group.
Signal is regarded as highly secure but state-sponsored hackers are believed to have the capability to intercept messages.
The Reuters and AP news agencies cited unnamed sources and said Mr Waltz is to leave after less than five months in the job.
His deputy, Alex Wong, is also said to be leaving.
Mr Waltz is a highly decorated veteran of the special forces and the first Green Beret to serve in Congress.
The 51-year-old is 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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