If rumours are to be believed that Kristen Stewart confronted Katy Perry about Robert Pattinson, then the Twilight hunk better be ready as John Mayer might soon do the same with him.

John is reportedly peeved off by the closeness that Rob shares with Katy even as friends. Apparently, the 35-year old musician still pines for the Firework singer and feels that the only hindrance to a possible reconciliation is Kristen's recent ex.

Over the past weeks, there has been a handful of Rob and Katy sightings that are said to be making John feel uneasy. Just last month, the two were seen watching a Daughter concert together, and at one point were also caught crashing a wedding rehearsal in a courtyard near Katy's hometown.

It is no secret that Katy has always been Rob's go-to friend even during the well-publicised cheating episode with Kristen. Some sources say Katy is his "source of therapy," that Rob finds comfort in her company as she is everything his ex is not.

And now that he and Kristen seem to have parted ways for good, Rob is again turning to Katy for support. This, according to sources, is not making John happy.

In fact, sources say it's making him jealous! John has apparently not overcome his feelings for Katy even months after she dropped him, and her attachment to Rob is just making things more difficult. John is said to be displeased and wants Rob out of the picture.

A source told Belfast Telegraph recently that the Grammy award winning singer is determined to do everything just to have Katy back, so any trace of male competition irritates him especially if it's as heartthrob looking as Rob.

"He realizes their relationship was special and he misses her. He's desperate to win her back. John wishes things could go back to the way they were, but believes Katy's friendship with Rob is getting in the way of a reconciliation," the source said.

With all these jealousy talks, should there really be a cause for alarm? Some sources believe that Katy might not be too opposed either to the prospect of getting back with John.

In fact, the exes were recently seen together chatting up a storm during Memorial Day barbeque. A source even intimated to Us Weekly the noticeable spark that existed between the ex-couple.

"They were very flirty and having a really good time together. They have good chemistry," said the source.

Well, the decision lies in Katy's hands. Only she can decide who she wants to be with eventually. But for the time being, let John do what he pleases to keep competition out of the way.

As they say, he who deserves to win will win.

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