Britney Spears and Kevin Federline 'Talk Dirty Over The Phone'

Britney Spears and her ex-husband Kevin Federline have been "talking dirty over the phone" during late-night calls, according to British tabloid reports.

The pair -- who have two sons together -- divorced in July last year.

But they have since been indulging in "marathon phone sex sessions" -- and are trying to keep their new-found friendship under wraps in a bid to avoid causing a scandal, reports the News of The World.

A source tells the publication, "It's early days, but there is certainly still something between them.

"They’ve been talking dirty over the phone and about how much they'd loved each other and how it all went wrong.

"They now speak at least every other day and Brit makes excuses to call Kevin, saying it's about the boys.

"He thinks she is getting back to her old self.

"But they're worried what it must look like after their break- up descended into such a bitter divorce. They want to keep it to themselves to see how well they're getting on before making any grand announcements."

Spears, 26, is due to release her sixth studio album, Circus, in December.

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