Andrew Garfield, Robert Pattinson Can’t Stand Each Other!

Robert Pattinson; Andrew Garfield Dominique Charriau/WireImage.com; Jeffrey Mayer/WireImage.com

British stars Andrew Garfield and Robert Pattinson are hardly best mates!

"The truth is, Andrew can't stand Rob," a source tells Us Weekly. "Andrew hates that they're put in the same category because they're both English and around the same age."

The sour sentiments seem to be mutual. At the June 23 wedding of their producer pal Kevin Turen, Pattinson, 26, and Garfield, 28, spent much of the night ignoring each other, says a witness.

"They don't enjoy hanging out," adds the observer. "Andrew considers himself a 'serious actor' and sees Rob as the equivalent of a cheesy boy bander because of Twilight."

Still, a third source chalks up the tension to a healthy Hollywood rivalry.

"Both like intense parts and go after the same roles," says the insider. "They're just naturally competitive."

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