Deputy Prime Minister and Liberal Democrat leader Nick Clegg has confirmed he will hold a meeting later today to decide whether to suspend Mike Hancock, who has been accused of sexual assault in a High Court civil action.
Mr Clegg said that "as leader of the party, you have got to react when allegations of this seriousness are made".
I immediately asked our chief whip to start disciplinary proceedings, including the possiblity of suspending the party whip.
The next step is that a meeting is held, between myself, my deputy Simon Hughes, the chief whip and Mike Hancock, and I am hoping to do that today at the very earliest opportunity.
As leader of the party, you have got to react when allegations of this seriousness are made, you can't just sit there on your hands.
Mr Clegg, who was speaking on LBC, added that: "The nature of the allegations are very serious, and they are allegations at the moment, I have got to stress that."
Mr Hancock denies the claims.
Mike Hancock, the MP for Portsmouth South, who is facing disciplinary procedures from his party over alleged inappropriate behaviour has said he will vigorously defend himself.
He told our political correspondent Phil Hornby that the first he heard about the decision to take action against him at 10pm last night when the Lib Dem chief whip summoned him to a meeting next week.
The Lib Dems could decide to withdraw the whip - in other words, to kick him out of the party - but Mr Hancock insists he has done nothing wrong. He has said he will not be "bullied" out of his job.
Deputy Prime Minister Nick Clegg has started "disciplinary procedures" against a Liberal Democrat MP accused of sexual assault in a High Court civil action.
Mike Hancock is being sued over alleged inappropriate conduct with a constituent after she contacted him for help in a neighbour dispute.
Mr Hancock, who vigorously denied the claims, 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.
The Portsmouth South MP Mike Hancock is to face disciplinary procedures, Lib Dem leader NIck Clegg announced tonight. It follows an investigation by party officials into allegations of inappropriate behaviour by Mr Hancock.
He could face having the Lib Dem whip being withdrawn - in other words, being kicked out of the party. But that would not necessarily trigger a by-election as he could continue as an independent MP. Mr Hancock has denied doing anything wrong.
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