Pattinson was heartbroken after Stewart was caught cheating on him with director Rupert Sanders in July last year. Even though the couple reconciled, they parted ways for the final time this year.
Katy Perry was spotted with Robert Pattinson on a number of occasions post his breakup, fuelling rumours of romance between them.
"I sent her (Stewart) a text message saying, 'I know you've seen all this stuff but you know I would never disrespect you. I'm not that person. I'm just trying to be a friend to him but it is unfortunate that I do have a set of t*ts'," Britain's ELLE magazine quoted Perry as saying.
Meanwhile, Perry is back with singer John Mayer after a brief split.