The Roar singer says she's a huge fan of the Locked Out Of Heaven singer and hopes they can get together in the studio soon.

Speaking to E! News, the 28-year-old Perry said: ''I've always said I'd wanna collaborate with Rihanna, but I'd love to collaborate with Bruno Mars. I always say, 'When I grow up, I wanna be the female version of Bruno Mars', cause he's so wildly talented in showing everybody that he has so much diversity in him.''

Katy also spoke about her new album Prism revealing that while it will still be a pop album, fans can also expect it to be a lot more personal than her previous release.

She said: ''I'm very proud of this record. It's very exciting. It's gonna make you dance, just like the last one but it's a lot more self-reflective.''