A young girl has told a jury she was ordered to film a woman carrying out sex acts which were screened on an internet chatroom.

The girl, who cannot be named, told a jury at Oxford Crown Court yesterday that she pointed a web camera as Christine Nicolson obeyed sexual requests on a chatroom in February 2005.

Nicolson, 53, who works at Stagecoach in Oxford, denies inciting a child to perform a sexual act and engaging in sexual activity in the presence of a child.

The girl told the jury via a videolink she was on a chatroom called Pal Talk when a man masquerading as a teenage boy made a lewd suggestion.

Nicolson moved her away from the computer screen then began performing sexual requests as the man watched on a web camera, she added.

She said: "I moved the web camera so he could see what she was doing. I was doing whatever he told me to do. I was reading the instructions that were typed on the screen."

Defending, Sailesh Mehta, asked the girl whether she had made the story up.

She replied: "I am not a liar."

The girl also told the jury Nicolson changed her clothes three times, including wearing a nightie and a string vest as she performed acts via the web cam.

Nicolson, of Cholesbury Grange in Headington, Oxford, and the man also tuned in to a website which screened pornographic movies while she was in the room, she added.

The trial continues.