American president Barack Obama has said that Michael Sam has shown "real sportsmanship" by announcing that he is gay.

The defensive end, who is entering this year's Draft, came out in an interview at the weekend and will become the league's first openly gay player if he signs with a team this off-season.

Obama said on his official Twitter page: "Congratulations on leading the way, @MikeSamFootball. That's real sportsmanship."

Sam, who made 11.5 sacks in his senior college season for the Missouri Tigers, has also received support from players already in the league since making the announcement.