Keira Knightley's naked confidence

Keira Knightley has no problem going nude in front of the camera.

The 23-year-old actress was happy to whip her bra off during a sex scene with Cillian Murphy in 'The Edge of Love'.

She said: "It was very simple. It was a sex scene and I never like them when they've got bras on. So when asked I said, 'alright

then'."

This isn't the first time Keira has stripped off in a movie. The British star previously filmed steamy scenes for 'Domino' and

'Atonement'.

While the actress is happy to bare her flesh on the big screen, she is terrified of singing in front of the cameras.

Keira, who has previously spoken about her reluctance to sing in 'The Edge of Love', is set to receive singing lessons for the role

of Eliza Doolittle in the remake of 'My Fair Lady'.

The actress is determined her vocal abilities will be in tip-top shape when she belts out the movie's classic songs, including 'The

Rain In Spain' and 'Wouldn't It Be Loverly?'.

My 'Fair Lady' is due to start shooting in 2010.