Biden accuser says he 'should take the polygraph'
In an interview with Megyn Kelly, Tara Reade says she hopes the Democratic presidential candidate will "step forward and be held accountable".
Ms Reade, now 56, worked as a staff assistant to Mr Biden from 1992-93 when he was a senator for the US state of Delaware.
She accuses him of sexually assaulting her 27 years ago.
Joe Biden denies the accusation.