Liberal Democrat MP Mike Hancock has quit the party whip while he contests allegations of sexual assault at the High Court.
Mr Hancock is being sued in a civil action by a "vulnerable" constituent, who accused him of sexual assault after she contacted him for help in a dispute with a neighbour.
A Liberal Democrat spokesman said: "Mike Hancock has chosen to resign the party whip while he defends himself against very serious allegations in a High Court civil action.
"Mike Hancock strenuously denies the allegations made in the civil case and intends to clear his name in court."
Mr Hancock was arrested by police over the allegations in 2010 but no action was taken as the Crown Prosecution Service said there was insufficient evidence for a prosecution.
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