Audrina Patridge on Kristin Cavallari: “I Don’t Like Her”

Move over, Lauren and Heidi. A new feud has emerged on The Hills: Audrina Patridge vs. Kristin Cavallari.

"I don't like her," Patridge confessed Thursday on Ryan Seacrest's KIIS-FM radio show.

Meow! Check out reality TV's biggest catfights of all time

She confirmed the two had a fight the first day of filming bonus episodes of the MTV show (it has been rumored that Cavallari has been pursuing Patridge's ex, Justin Bobby). Patridge was mum on what went down, but told Seacrest, "When someone gets in my face, I have to defend myself. And, you guys, I mean, I can't say much. They'll show it, but I mean, all I have to say is, it's really pathetic and desperate what people will do when the cameras are around." "It was my birthday, and I was like, Oh, my God. Is this what we're going to have to deal with?'" she added.

Look back at famous Hills scandals

Patridge wouldn't open up about her recent fling with Star Trek hottie Chris Pine. Us Weekly reported that the two met at ShoWest in Las Vegas in early April. On May 15, she was spotted leaving his L.A. apartment building. "There's always speculation of anyone I hang out with or anything I do," a coy Patridge told Seacrest.

See baby photos of The Hills stars

Pressed for more, she replied, "My lips are sealed."

Look back at unforgettable Hills hook-ups

Still, she said, "From Justin Bobby, I think any guy is an upgrade. I mean, I've learned so much since that relationship."

Sign up now for the Us Weekly newsletter to get breaking celebrity news, hot pics and more delivered straight to your inbox!

Want stories like these delivered straight to your phone? Download the Us Weekly iPhone app now!