The 36-year-old came close to joining Spurs on loan last season.
Beckham said: “I have always said I have played for the biggest club in England and I wouldn’t like to play against them (United).
“I am 36 and still feel good and fresh but I can’t see it happening.
“The Tottenham thing didn’t happen for a reason. I only want to be known as a Manchester United player and that’s the way it will stay.”