The surprise move on Friday comes amid a long-simmering fued between Priebus and new White House Communications Director Anthony Scaramucci, who lambasted him in an interview with the New Yorker this week.
Speaking to reporters, Trump called Priebus a “good man” but called Kelly a “star.”
“Reince is a good man,” he said at Andrews Air Force Base outside of Washington D.C. after a trip to New York to talk about his push to end gang violence.
“John Kelly will do a fantastic job. General Kelly has been a star, done an incredible job thus far, respected by everybody. He’s a great American,” he said.
Trump announced the decision on Twitter as his plane landed at Andrews.
Priebus had initially gotten into a van with White House Policy Adviser Stephen Miller and White House Social Media Director Dan Scavino on the tarmac, but shortly after, the two men left the van and left Priebus alone, according to the White House pool.