National Security Adviser H.R. McMaster has resigned from his position in the Trump administration, the latest shake up of high-ranking officials within the White House.
Trump announced on Thursday that John Bolton, former U.S. ambassador to the United Nations, will assume the role on April 9.
“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 in a message on Twitter.
The news comes after President Donald Trump fired Secretary of State Rex Tillerson earlier in March.
McMaster and Trump have reportedly not seen eye-to-eye on various issues either.
The three-star Army general told an audience at a Munich Security Conference last month that evidence of Russian meddling in the 2016 presidential election is indisputable, and referring to the indictment of 13 Russians said, “with the FBI indictment, the evidence is now incontrovertible.”
The president responded in a tweet, saying his top aide did not include all the details.
“General McMaster forgot to say that the results of the 2016 election were not impacted or changed by the Russians and that the only Collusion was between Russia and Crooked H, the DNC and the Dems," Trump wrote.
McMaster became national security adviser in February 2017 following the resignation of Michael Flynn. He previously led the Army Capabilities Integration Center before his appointment, and served in the Persian Gulf War and those in Iraq and Afghanistan.
The president hinted at potential forthcoming changes to his Cabinet following the announcement of Tillerson’s ouster.
"I've gotten to know a lot of people very well over the last year," Trump told reporters at the White House, "and I'm really at a point where we're getting very close to having the Cabinet and other things that I want."
Sources told Fox News other departures from the administration could include Department of Veterans Affairs Secretary David Shulkin and Chief of Staff John Kelly.