Are Katy Perry and Taylor Swift really 'enemies'?

"Watch out for the Regina George in sheep's clothing"... the latest clue that two of pop's biggest stars might actually be 'ENEMIES'.

Katy Perry wrote the cryptic tweet, referring to the nasty character from the film Mean Girls, after speculation about her and Taylor Swift.

It's after Swifty opened up to Rolling Stone about being "straight-up enemies" with an unnamed female artist.

"For years, I was never sure if we were friends or not," she says.

She told the magazine the track 'Bad Blood' on her upcoming album, 1989, is about the "mystery" celeb.

"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?'"

Then last year... "She did something so horrible, I was like, 'Oh, we're just straight-up enemies.' And it wasn't even about a guy".

She says the pop feud is all because of "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."

So is it Katy Perry?

Well, these fans all seem convinced...

It's widely reported that three of Taylor's dancers, who had previously worked with Katy, left part way through her tour last year to work with Katy again.

Both singers have also been linked to singer John Mayer in the past.

And Taylor could be seen to have made a dig at Katy during the Roar 'plagiarism' row.

After some accused Katy of stealing from Sara Bareilles' "Brave", Taylor invited Sara on stage to sing the song, calling it "so original".

So, you decide...

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