Robert Pattinson and Kristen Stewart are reportedly feuding over his rumored Katy Perry hookup. A recent edition of OK! Magazine claims that Stewart left ex-boyfriend Pattinson a nasty voice message over whom he has been choosing to date.

A source told the magazine, "She flipped out on his voicemail. There are thousands of girls in L.A. Why does Rob need to hook up with her friends? He's got to stop using her circle as a dating pool."

Stewart was likely referencing the Twilight actor's rumored hookup with Katy Perry. Neither celebrity has confirmed or denied the allegations.

One source who spoke with The Sun claims that their romance has been a long time in the making, adding, "Katy and Rob are the best of friends with a very strong sexual chemistry. They care a lot about each other but have always been careful not to upset Kristen. But Kristen's off doing her own thing and accepting it's time to move on. Katy and Rob have been hanging out all weekend and making plans for Easter, too...Friends genuinely want to see them get it together properly."

It seems there are plenty of other women who would date Pattinson, including his good friend Holliday Grainger.

Grainger recently said in an interview, "I've known him since his pre-Twilightdays when he was a normal person and it was still like, 'ooh you're playing Cederic Diggory. He's managed to keep very level headed and normal. I don't understand how."

'The Borgias' actress said, "I can't fathom the idea of living a life like he lives. On the set of Bel Ami in Budapest there would be hundreds of screaming girls there at 5am and they would still be cordoned off when we finished. He had to move hotels because there were so many people outside his. One day he was signing autographs on the way home from work at 6am after a night shoot. Bless him, that's an extra level of hard."