President Donald Trump announced Friday that Secretary of Homeland Security John Kelly will be his new chief of staff.

“I am pleased to inform you that I have just named General/Secretary John F Kelly as White House Chief of Staff. He is a Great American….,” Trump tweeted about the former Marine Corps general. “John has also done a spectacular job at Homeland Security. He has been a true star of my Administration.”

Kelly, who has little political experience, will be taking on a job historically suited for Washington insiders.

Trump also tweeted his appreciation for his outgoing chief of staff. “I would like to thank Reince Priebus for his service and dedication to his country. We accomplished a lot together and I am proud of him!”

President Trump brought on Anthony Scaramucci as his communications director last week, and since then, Scaramucci has been publicly feuding with Priebus. Scaramucci told The New Yorker in an interview published Thursday that Priebus is a “paranoid schizophrenic.” Priebus told CNN’s Wolf Blitzer shortly after Trump’s tweets that he had actually resigned Thursday. Priebus said he offered his resignation and Trump “accepted it.”

Several Priebus allies — former press secretary Sean Spicer, former assistant press secretary Michael Short, and former deputy chief of staff Katie Walsh — have been pushed out or resigned from the Trump White House.