General H. R. McMaster has been fired as National Security Advisor. He will be replaced by former interim U.N. Ambassador John Bolton effective April 9.

President Donald Trump announced the position change on Twitter.

“I am very thankful for the service of General H.R. McMaster who has done an outstanding job & will always remain my friend,” Trump wrote. “There will be an official contact handover on 4/9.”

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Bolton was previously the interim U.S. Ambassador to the United Nations, and he contributes to Fox News. He was unable to receive Senate confirmation so former President George W. Bush gave him a recess appointment. 

“It is an honor to be asked by President Trump to serve as his National Security Advisor,” Bolton said in a statement. “I humbly accept his offer. The United States currently faces a wide array of issues and I look forward to working with President Trump and his leadership team in addressing these complex challenges in an effort to make our country safer at home and stronger abroad.”

McMaster was rumored to be on the outs with Trump a few weeks ago, as he had previously asserted that Russia meddled in the 2016 Presidential election. Bolton will be the Trump Administration’s third National Security Advisor.