Robert Pattinson and Kristen Stewart avoid public displays of affection because they don't want their relationship to be the centre of attention, it's claimed.

The Twilight couple would reportedly rather people believed they were friends and co-stars rather than real-life lovers.

"Yes indeed, they are a couple," says an insider. "Rob and Kristen do not even show public displays of affection in front of their friends because they do not want to be talked about."

Isn't it a bit late for that?

The source adds to E! News: "The only time you see them being affectionate towards one another is when they are doing a scene together.

“Aside from that, one could still assume they are just friends, and that is what they want outsiders to continue believing.”

Rob and Kristen were joined on stage by Taylor Lautner to unveil the latest New Moon trailer at Sunday's VMAs.

Rob and Kristen in pictures