"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 and a Great Leader. John has also done a spectacular job at Homeland Security. He has been a true star of my Administration," Trump said in a series of tweets Friday afternoon.
In a statement later on Friday, Priebus said it "has been one of the greatest honors of my life to serve this President and our country."
"I want to thank the President for giving me this very special opportunity," the statement continued. "I will continue to serve as a strong supporter of the President's agenda and policies. I can't think of a better person than General John Kelly to succeed me and I wish him God's blessings and great success."
Senior White House officials with direct knowledge of the changes happening in the West Wing said the president told Priebus two weeks ago he wanted to make a change.
Priebus spoke to CNN about two hours after the announcement was made, and he repeatedly said that he resigned but noted that the president wanted to go in a different direction.
“It was something I think the White House needs. I think it’s healthy, and I support him in it,” Priebus said of the shift.
Appearing on Fox News’ “Hannity” on Friday night, Priebus said he spoke with Trump about who would be his successor.
“We had a good talk yesterday. I resigned, he accepted it,” he said. “And we started working together and talking quite a few times about who would be a great pick to come in here and be the chief of staff, and I can't think of anyone better than a four-star general, John Kelly.”
Priebus added that he feels “hitting a reset button” is “a good thing.” He declined to comment on any controversy surrounding incoming White House Communications Director Anthony Scaramucci.
“It's just getting in the mud, and I think the palace intrigue stuff is annoying, and I think it's a distraction and it takes away from the president's agenda,” he said.
He released a statement thanking "the tremendous men and women of DHS."
"When I left the Marines, I never thought I would find as committed, as professional, as patriotic a group of individuals. I was wrong. You accomplish great things everyday defending our nation and I know your exceptional work will continue," Kelly said.
Kelly added that he is "honored to be asked to serve" as the president's chief of staff.
Kelly will start as chief of staff on Monday morning and White House press secretary Sarah Sanders said that a Cabinet meeting will follow his swearing-in.
Trump praised Kelly just this afternoon at an event with law enforcement officials on Long Island in New York.
Trump said Kelly "has done an incredible job of secretary of homeland security. Incredible. One of our real stars. Truly one of our stars. John Kelly is one of our great stars."
Trump thanked him for "his service" in a tweet.
After walking off Air Force One at Joint Base Andrews in Maryland, Trump briefly spoke to reporters.
"Reince is a good man. John Kelly will do a fantastic job. General Kelly has been a star. Done an incredible job thus far. Respected by everybody. A great, great American. Respected by everybody. Reince Priebus [is] a good man," Trump said.
Trump has felt his team needed a chief of staff who could help push his agenda forward and get the West Wing in shape. After that conversation, the president began weighing his options and ultimately decided on his first choice – Kelly – the officials told ABC News.
The president’s plan was to make this change around the congressional recess with the goal of having a vacation period to get things in shape heading into the fall, the officials said, noting that the fact that new communications director Anthony Scaramucci has joined the team is not connected to Priebus leaving.
As one source put it, “This was a long time coming, period.”
"Reince Priebus — if you want to leak something — he’ll be asked to resign very shortly," Scaramucci told reporter Ryan Lizza, according to The New Yorker article.
The day before The New Yorker article was published, Scaramucci posted a tweet, which he later deleted, where he tagged Priebus and wrote that he would be contacting the FBI and Department of Justice to investigate leaking.
Priebus was one of the members of Trump's senior staff who had the most experience working in Washington politics, having previously served as the Republican National Committee chairman before joining the Trump team during the transition.
He had ties to key members of the Republican Party, like House Speaker and fellow Wisconsinite Paul Ryan, but his support base within the White House is believed to have eroded in recent weeks. Katie Walsh, who served as Priebus' deputy chief of staff at the White House, left in March, and on July 21, press secretary Sean Spicer resigned. Both Walsh and Spicer worked with Priebus at the RNC.