R Kelly and his lawyers have been hit with the accusations of a key witness claiming she was involved in a three way sex act with R Kelly and an underage girl.

Distressed witness, Lisa Van Allen cried in the stand as she gave her testimony alleging R Kelly had offered her $250,000 to conceal the video recording of him having sex with an underage girl.

Van Allen said Kelly told her the underage girl was16 and had videotaped their sexual trysts together more than once.

In her testimony Van Allen, 27, told how Kelly always carried a duffel bag everywhere containing the videos of his homemade sex tapes.

She also testified that she was payed $20,000 when she handed over the tape in a hotel room.

The defence lawyers accuse Van Allen of attempting to extort the troubled singer.