President Donald Trump in "60 Minutes" interview to air Oct. 14

"I don’t know, he hasn’t told me, but I have a very good relationship with him," the president said in a "60 Minutes" interview set to air Sunday evening when asked by Leslie Stahl about Mattis' potential departure.

"It could be that he is. I think he’s sort of a Democrat, if you want to know the truth. But General Mattis is a good guy, we get along very well. He may leave, I mean at some point, everybody leaves."