The coalition government that has ruled Britain since 2010 has been shaken by the surprise resignation of a senior minister for an alleged crime committed nearly a decade ago.

Energy Secretary Chris Huhne on Friday became the third member of Prime Minister David Cameron's Cabinet to step down. He, along with his former wife, Vicky Pryce, stand accused of perverting the course of justice involving a traffic offense in 2003.

It is alleged that after being stopped for speeding, Huhne told authorities that Pryce, his-then wife, was actually behind the wheel so that he would avoid losing his driver's license. Pryce, according to the charges, falsely agreed that she was the driver.

Huhne is a senior member of Britain's Liberal Democrat party. Both he and Pryce, who say they are innocent, are due in court February 16.

Prime Minister Cameron praised Huhne for the contributions he made to the government but said Huhne had made the right decision to step aside.

Huhne, as energy secretary, played an important role in December's climate change talks in Durban, South Africa, that produced an agreement on cutting greenhouse gas emissions.

Another Liberal Democrat minister resigned just days after the party joined with the Conservatives in 2010 to form the ruling coalition. Defense Secretary Liam Fox resigned last year.

Huhne is being replaced by a fellow party member, Ed Davey. Under the coalition agreement, the Liberal Democrats hold five Cabinet posts.