Katy Perry and Kristen Stewart are reportedly fighting over a major role in the upcoming as-yet-untitled Freddie Mercury movie.

As we reported earlier this summer, Perry has been eyeing the part, but now she's got stiff competition. 'Twilight' actress Kristen Stewart, as well as Lady Gaga, are said to be gunning for the part of Mary Austin, who was in a six-year relationship with the Queen frontman before he admitted he was gay.

According to Hollywood Life, a source told Star magazine, “Lady Gaga, Katy Perry and Kristen Stewart are on the short list for Mary, who played a huge role in Freddie’s life. They all desperately want the part, and it’s getting ugly!”

Sacha Baron Cohen has been cast as Mercury, and will reportedly choose his leading lady, who the late singer once described as “the love of his life." However, rumors of cattiness may ruin the stars' odds of landing the coveted role.

“With the girls fighting like this, it’s just hurting their chances of getting the part," the source added. "It’s unprofessional, and Sacha is tired of the back-and-forth -- he wants to choose one of them and be done with it.”

Mercury remained close with Austin until his death in 1991 from complications with AIDS. The movie could see a 2014 release, and, according to screenwriter Peter Morgan, fans will get to see the personal side of the iconic musician. "I didn’t want to write about a man dying from AIDS," he said. "Luckily, when I looked into Mercury’s life, I found a good story in that window."

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