Sri Lanka, May 1 -- U.S. President Donald Trump's national security adviser Mike Waltz is being forced out of his job, four people briefed on the matter said on Thursday, in the first big shakeup of Trump's inner circle since he took office in January.

Waltz's deputy, Alex Wong, an Asia expert who was a State Department official focused on North Korea in Trump's first term, is also leaving his post, two people told Reuters.

A 51-year-old former Republican lawmaker from Florida, Waltz faced criticism inside the White House when he was caught up in a March scandal involving a Signal chat among top Trump national security aides.

It was not immediately clear who would take over from Waltz, but one option included U.S. special envoy Steve W...