Jenkins fretted over 'Doctor Who' kiss

Katherine Jenkins has described a kissing scene involving her character in the upcoming Doctor Who Christmas special as the most terrifying moment of her career.

The opera singer was required to kiss actor Danny Horn as part of the festive instalment, but she admits that she was uncomfortable about filming the intimate moment.

"The kissing was the most stressful part of the whole thing," she said. "My mum's got to watch that on Christmas Day!

"I really don't know how it's going to come across. I just want to get that bit out of the way. It was by far the most nerve-wracking thing I've ever done."

Jenkins went on to say that the scene was even more intimidating than her performance in front of Pope John Paul II in 2003, according to The Sun.

The 30-year-old also recalled how Matt Smith mischievously decided to ruin the scene a number of times in order to have Jenkins and Horn do several takes.

"He kept doing it on purpose going, 'Oh sorry, I messed it up. You'll have to do it again,'" Bang Showbiz quotes her as saying.

Although Jenkins's boyfriend - TV star Gethin Jones - said that he had to close his eyes during her on-screen kiss, the actress admitted that her friends' reactions to seeing the scene made her feel more comfortable.

She added: "I could hear my friends laughing when the kissing parts came on so that made me feel a little bit better."

Doctor Who's one-off special, entitled 'A Christmas Carol', airs on BBC One on Christmas Day at 6pm.