General James Mattis, the US defence secretary widely regarded as a moderating influence on President Donald Trump, may leave the administration hinted the American leader who said he suspects the military veteran is a Democrat

In an interview aired on Sunday, Mr Trump seemed to suggest an inevitability about the four star general's departure while adding that the two men had a "good relationship".

It is not the first time his exit has been discussed in Washington, although not publicly by Mr Trump, and just a few weeks ago the four star general was forced to dismiss reports of his impending departure.

But when asked during the CBS 60 Minutes conversation recorded on Thursday, if he thought Gen Mattis was heading for the door, the president was circumspect.

“Well, I don’t know. He hasn’t told me that. I have a very good relationship with him. I had lunch with him two days ago," he said.

“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. Everybody. People leave. That’s Washington.”