11/05/2012 02:12 pm ET Updated Nov 05, 2012

Katy Perry, Rihanna Rift: Singers Have Fallout Over Chris Brown (REPORT)

Katy Perry and Rihanna were best buds, but their friendship isn't doing too well these days and Chris Brown may be to blame.

According to the New York Daily News, Rihanna's relationship with Chris Brown has put a strain on her friendship with the "Part of Me" singer, and the two are "barely talking."

Sources close to Perry revealed "there has been tension" between the pop stars since Rihanna reunited with Brown, and she even skipped out on Perry's recent Halloween party. According to the source, Perry, like many others, fear that Rihanna is " making a huge mistake and doesn’t want to be part of it.”

Perry and Rihanna were last spotted together at the MTV Video Music Awards in September -- the same award show where Rihanna publicly planted a kiss on Brown, much to everyone's surprise. The couple broke up after Brown assaulted the singer in 2009, but it's since been rumored that the two have rekindled their friendship if not a full romantic relationship.

It's a decision that reportedly has Perry concerned for her friend, and it's not the first time the friendship has been strained because of Brown.

"We’ve had dinner, and that’s about it. I didn’t reach out to her after the incident," she told MTV News in 2009 of Brown's assault on Rihanna. "I think she is doing fine. I don’t know. Her personal life has probably already been blown out of proportion. I don’t really have to go into that. I’m sure she probably wants a break."

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