Former Lib Dem Cabinet minister Chris Huhne pleaded guilty to perverting the course of justice today after years of denials over a simple speeding ticket.
The disgraced MP left his party in disarray and could face jail after admitting to speeding down a motorway a decade ago - and, when caught on camera, allegedly convincing his then wife Vicky Pryce to take the fall.
The former energy secretary had been expected to plead not guilty at Southwark Crown Court in London today, having repeatedly called the allegations "simply incorrect" since they emerged in 2011.
Mr Huhne has said that he will also resign his Eastleigh seat.
"I am unable to say more as there is an outstanding trial, but having taken responsibility for something which happened 10 years ago, the only proper course of action for me now is to resign my seat at Parliament, which I will do very shortly."
The statement follows repeated attempts to have the case thrown out of court, with barrister John Kelsey-Fry telling the court the prosecution's case was circumstantial - "at best gossamer-thin."
But prosecutors said Mr Huhne had a history of speeding, with nine points on his licence already and close to losing it.
He had flown into Stansted airport less than an hour before his BMW was snapped on the M11.
Meanwhile Ms Pryce had spent the evening at the London School of Economics.
The trial continues, with both charged with perverting the course of justice.
Ms Pryce has pleaded not guilty on grounds of marital coercion.
Party leader Nick Clegg said he was "shocked and saddened" and that Mr Huhne had made the "right decision" to resign.
Labour MP Simon Danczuk, who first reported Mr Huhne to the police over the allegations, condemned the former policing spokesman for drawing out his plea at the public's expense.
"Chris Huhne had the opportunity to plead guilty in front of magistrates over six months ago.
"Instead, he decided to put the Crown Prosecution Service to no doubt considerable expense in preparing the case for trial only for him to change his mind and suddenly plead guilty.
"I sincerely hope the judge in sentencing will make Huhne repay these wasted costs.
"None of us are above the law, including ministers," he said.
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