Kevin Spacey is being investigated over a third allegation of sexual assault.

The disgraced 'House of Cards' star was previously accused of sexually assaulting a man in Lambeth, South London, in 2005, and was also under investigation by Scotland Yard detectives over another incident in 2008, and the police have now confirmed they investigating the same person over an allegation in Westminster, also from 2005.

The Metropolitan Police said in a statement: ''On 13 December we received an allegation that the man sexually assaulted a man (Victim 3) in 2005 in Westminster. Officers from the Child Abuse and Sexual Offences Command are investigating.''

In addition to the police complaints, the Old Vic theatre - where Spacey was creative director from 2004-2013 - previously revealed they had had more than 20 people come forward to make allegations about the 58-year-old actor during his tenure there.

The theatre claimed a ''cult of personality'' had existed around Spacey, and his status and stardom had stopped people, in particular young actors and junior staff, from speaking out about his alleged actions.

They said in a statement: ''Despite having the appropriate escalation processes in place, it was claimed that those affected felt unable to raise concerns and that Kevin Spacey operated without sufficient accountability.

''This is clearly unacceptable and the Old Vic truly apologises for not creating an environment or culture where people felt able to speak freely.''

Of the 20 testimonies, all but two incidents were said to have occurred before 2009 and just one had previously made a complaint.

The Old Vic also stressed that ''no legal claims, formal grievances, formal disputes, settlement agreements or payments made or authorised were made at all in relation to Kevin Spacey during his tenure''.

The 'American Beauty' actor has yet to comment on the allegations against him.