Kevin Federline is alleged to have been having an affair with a porn star for a month before wife Britney Spears filed for divorce.

The wannabe rapper allegedly met "exotic dancer" and former X-rated actress Kendra Jade in Las Vegas in December 2005, while Britney was visiting her family in Kentwood, Louisiana, and the two stayed in touch.

The pair reportedly started their affair in October 2006.

A source told America's Star magazine: "Kev and Kendra had sex at their friend's apartment multiple times, starting in early October.

"Their friend would phone Kendra and a few other girls to come hang out, and it would always end up with Kevin and Kendra heading off to the spare bedroom! They're like friends who have sex."

However, Kendra has denied the claims, saying: "I'm in a committed relationship."

Britney filed for divorce on November 6 citing irreconcilable differences.

She and Kevin have both applied for sole custody of their two sons, one-year-old Sean Preston and ten-week-old Jayden James.