Trump told The Daily Caller that "there's no reason for it" but he also feels Nike's ability to make its own business decisions "is what this country is all about."
Trump has been a frequent critic of protesting NFL players. He has loudly urged the league to suspend or fire players who demonstrate during the anthem.
The Republican president is also a key figure in Kaepernick's grievance case against the league. Some NFL owners have said Trump made clear to them his feelings about demonstrations during the anthem and his intention to continue to raise the issue.
Kaepernick is arguing the owners colluded to keep him off any roster.