Strictly Come Dancing judge Darcey Bussell has described her first appearances on the show as "terrifying".

The former Royal Ballet principal dancer joined the BBC dancing contest in 2012.

Speaking to The Times Saturday Review, she told of the nervousness she experienced during the early part of her Strictly career.

She said: "In the beginning it was terrifying; live television is terrifying.

"I didn't know how to express myself sitting in a chair where I couldn't move.

"It took me a while to understand that I had a voice as well. The guys were incredibly supportive and they made me feel very much at home, despite my nerves and my hiccups."

The 45-year-old, who will return to the judges panel when the new series of starts this autumn, conceded she is seen as "the nice judge".

She said: "I will say something if I believe someone is not trying hard enough, but generally I'm more sympathetic to the contestants because I know what it's like to be flattened and demoralised.

"Criticism has been my life as a dancer and I don't want to do that to them. That won't help them come back next week."

The ex-ballerina is a special ambassador for Big Dance, a week-long celebration of dance including hundreds of events that starts today.

She said: "Dance has got to be part of the norm because it's a wonderful way to lift your spirits."

Darcey appeared alongside Boris Johnson at a Big Dance launch event earlier this week and was impressed with the Mayor of London's moves.

"He should keep dancing!" she said.