Maybe Taylor Swift is bitter that Justin Bieber mericlessly punk'd her last year. Or maybe she's simply a really good friend to Selena Gomez and steadfastly disapproves of Jelena dating and/or reuniting and isn't hiding it. Or maybe she's mad that he beat her out for the Milestone Award. In any case, Swift further dissed the Biebs in an interview at the 2013 Billboard Music Awards.

Swift was caught sticking her tongue out in disgust when Sel stopped to greet her ex with a kiss backstage at the awards ceremony in a video that was widely circulated. Now, interview footage from that night further indicates Swift's deeply developed disdain for the Biebs.

“Ohhh, you do not want to know!" Swift said when asked what she and her BFF Gomez were talking about that night. “You do not want to open that can of worms. Especially tonight.”

Ouch. That sounds a bit harsh, right?

Biebs, grab a catcher's mitt so you can catch that shade that T. Swizzle is throwing. Or maybe you better duck, since she's aiming at the pretty haired head o' yours.

The reporter joked that the confessional Swift should write a song about things, and she said, “No, it’s not [me] … I’m fine!”

We're dying to know the reason why Swift has turned on the Biebs so markedly. A Belieber, she is not.

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