Snoop Dogg appeared on Katy Perry's 'California Gurls' because she is a "bad bitch".

The 'Sensual Seduction' rapper worked with the risque pop star because he likes her attitude, and insists his input to the track - which became a number one single in the UK, US and Australia - was key to its success.

He told blackbookmag.com: "I worked with Katy because she's a bad bitch, but she needed a gangster to complete The Deal.

"She had a cake with no candles on it, then she put me on 'California Gurls', and it went to number one."

Despite appearing on tracks by Katy and Pussycat Dolls as well as enjoying a string of his own hit singles - including rap classics such as 'Gin And Juice', 'Signs' and 'Drop It Like It's Hot' - the 39-year-old star maintains he is no pop artist.

He said: "I'm probably the most popular rapper in the world, but I don't make pop music. I make gangsta s**t. I don't cross over to pop-pop crosses over to me.

"I don't ever aim for radio play. I make s**t that feels good to me, and if top 40 radio catches wind, then great. If they don't, I'm still gonna do what I gotta do."

Snoop Dogg was also today (02.03.11) announced as headliner of Britain's LoveBox festival, where he will perform his 1993 debut album, 'Doggystyle', in full.

Other acts also confirmed for the event - which takes place between July 15 and 17 in London - include Scissor Sisters, Kelis, The Drums, The Wombats and Example.