A French prostitute called Sabrina claims that BB's Nikki Graham joined her to perform a girl-only sex show in front of a group of rich clients for a fee of £800.

'We were doing everything to each other,' Sabrina alleges in a Sunday tabloid. 'She talked almost as much as she did the rest of the time.'

The high-class hooker also alleges that the reality TV star spent the night with men for a fee of between £200 and £1,000.

Nikki, 24, strenuously denies ever working as a call-girl. She admits that she did take three jobs as an escort in March this year but says she didn't have sex with any of the clients.

Nikki's agent says: 'Nikki has assured me the allegations made by the Sunday Mirror are untrue. She is taking this matter very seriously and is seeking legal advice.'