Why tongues are wagging about Kylie Minogue and Dr Who David Tennant

The pair were spotted making a secret visit to the Old Vic to watch Cinderella just before Christmas and I understand they speak regularly on the phone.

"They kept the visit top secret and slipped in and out before anyone in the theatre had a chance to notice an A-list star and a famous actor were in the stalls," I'm told.

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Tennant is currently dating 28-year-old Bethan Britton, who works for the BBC, while Kylie revealed in a recent interview that she has started dating again, though she wouldn't reveal any names.

Tennant ended his two-year relationship with Thunderbirds actress Sophia Myles last October.

The couple reportedly found it too difficult to conduct a long-distance relationship as Myles found her film career meant her work was taking her increasingly in Los Angeles.

Tennant is gearing up for a busy year on the stage - in July he will star opposite Mariah Gale in Hamlet at RSC's Courtyard Theatre in Stratford-Upon-Avon from July.

After his run as the tragic Danish prince, Tennant will then appear in a second RSC production in Love's Labour's Lost in the autumn.

Meanwhile, Kylie remains single since splitting from long-term love Olivier Martinez last February.

The French actor supported the pop star through her battle with breast cancer, but announced their split shortly before Valentine's Day after four years together.