It would appear the claws are coming out!

Katy Perry added fuel to the rumors she is the "frenemy" Taylor Swift mentioned in a revealing Rolling Stone interview by tweeting a reference to Mean Girls.

"Watch out for the Regina George in sheep's clothing…" the "Roar" singer tweeted as a reference to the famous catty girl character in the 2004 comedy. It seems the Grammy winner all but confirmed she was the girl T-Swizzle was talking about when she explained her bad blood with an unnamed celebrity.

"For years, I was never sure if we were friends or not. She would come up to me at awards shows and say something and walk away, and I would think, 'Are we friends, or did she just give me the harshest insult of my life?'… She did something so horrible. I was like, 'Oh, we're just straight-up enemies.' And it wasn't even about a guy! It had to do with business. She basically tried to sabotage an entire arena tour. She tried to hire a bunch of people out from under me. And I'm surprisingly non-confrontational — you would not believe how much I hate conflict. So now I have to avoid her. It's awkward, and I don't like it," the "Shake It Off" songstress confessed to the mag.

It's worth noting that both the pop princesses dated John Mayer, so we would guess boy drama plays at least a small role in their cat fight!