The "fireworks" appear to be over for Kristen Stewart and Robert Pattinson  but is Katy Perry to blame?

A source tells E! Online that Robert Pattinson and Katy Perry's connection is part of why Rob and Kristen parted ways recently.

Katy "played a role, as one of many reasons" for the break-up, reveals a source. 

Indeed, Katy has known Rob for quite some time, and the two had been partying together just before his birthday

Plus, there had been a rumor that Katy recently told Kristen that she would be interested in dating Rob if he and Kristen ever broke up. Uh-oh.

That said, a second source tells E! News that this is untrue, adding: "To bring Katy into this is just complete nonsense."

Either way, it seems that our "teenage dream" of Kristen and Rob getting back together is fading fast.

Source: E! News