CHRIS Huhne faces a jail term if found guilty of perverting the course of justice in connection with a 2003 speeding case but a possible return to government if he is innocent.

After months with the prospect of a criminal allegation hanging over his head – one he vehemently denies – the Energy and Climate Change Secretary yesterday morning became the first Cabinet minister in history to be forced from office by a criminal prosecution.

His resignation announcement came minutes after Keir Starmer, the Director of Public Prosecutions in England, took the unusual step of announcing the outcome of an official inquiry live on television.

Mr Starmer said that, after considering the material, there was sufficient evidence to charge the MP for Eastleigh in Hampshire – along with his ex-wife Vicky Pryce – with perverting the course of justice.

The charge relates to an allegation that Mr Huhne, then an MEP, persuaded Ms Pryce to take his penalty points for a speeding offence on the M11 in Essex.

The claim only emerged last year after the couple's 26-year marriage ended because of the politician's affair with his PR adviser Carina Trimingham.

Ms Pryce told a newspaper that her ex-husband had asked "someone" to take the penalty on his behalf to avoid losing his driving licence.

The matter was then reported to the police by Labour backbencher Simon Danczuk.

The charge carries a maximum sentence of life imprisonment but it is thought that were the former Secretary of State to be found guilty, he could be jailed for three to nine months.

Mr Huhne yesterday again denied the allegation, explained he was standing down from Cabinet to avoid a distraction to his government role and made clear he would mount a "robust defence" to the charge.

He described the decision of the Crown Prosecution Service (CPS) to press charges as "deeply regrettable" and said: "I'm innocent of these charges and intend to fight them in the court and am confident a jury will agree."

Meanwhile, Ms Pryce, a prominent economist, said she hoped for a "quick resolution".

The case will begin at Westminster Magistrates Court on February 16 and then transfer to the Crown Court, possibly the Old Bailey, with a full trial in the autumn.

Mr Huhne's departure forced David Cameron into a mini-reshuffle. Business minister Ed Davey is elevated to the Cabinet. Norman Lamb, formerly Nick Clegg's Chief of Staff, replaces Mr Davey at the Business Department and Jenny Willott joins the Government as a whip

Jo Swinson, the MP for East Dunbartonshire, becomes the Deputy Prime Minister's Private Parliamentary Secretary.

About an hour before the official 10am announcement, Mr Huhne was told that he would be charged. David Cameron was informed by the CPS around the same time as he was travelling to Plymouth. He spoke on the phone to the Energy Secretary, who formally resigned.

No 10 said the PM regarded Mr Huhne as a "valued colleague" with whom he had a "good working relationship".

Mr Cameron later said his former Cabinet colleague had "made the right decision, given the circumstances".

Mr Clegg, who beat Mr Huhne to the party's leadership in 2007 by 500 votes, was more effusive about his "close colleague".

He praised his "trailblazing work" on the energy brief and said he hoped he would clear his name so that he could "return to play a key role in government".

Mr Huhne has been the most vocal Cabinet critic of the Conservatives, privately and publicly, clashing on such issues as the AV referendum and Mr Cameron's EU treaty veto.

He is the third Cabinet minister the PM has lost in 18 months following the departures of David Laws and Liam Fox.

In Westminster terms, the Hampshire MP is a big hitter and will be a loss to his party in putting forward its case on policy at the top of government.

Mr Huhne is entitled to a severance payment of £17,207. It is not known if he will take it.