Lord Janner will be prosecuted for historical sex abuse against children, the Crown Prosecution Service confirmed today.

The CPS’s decision comes after a review by independent QC David Perry who recommended that a trial would be in the public interest.

It overturns a ruling in April by Alison Saunders, the director of public prosecutions, that Lord Janner was not fit to stand trial because he suffered from a severe form of dementia.

She made the ruling while acknowledging that there was sufficient evidence to charge the 86-year-old over allegations of offences dating from the 1960s to the 1980s.

Ms Saunders, who is facing calls for her resignation, said she accepted the outcome of the review and would now be bringing a prosecution.

The case, expected to start on August 7, is set to be a “trial of the facts” without Lord Janner in court, deciding only if the peer committed physical acts of abuse.

Solicitor Liz Dux, who represents some of the alleged victims, said: "This is a vindication of our efforts to challenge the DPP's original decision not to charge Janner, which was clearly not in the interest of justice".

Lord Janner has been a prominent figure in the British Jewish community and served as Labour MP for Leicester West for 27 years.

His family have said he is “entirely innocent of any wrongdoing”.