CHRIS HUHNE, the dark horse for the Liberal Democrat leadership, faces accusations of betraying his collegues by reneging on a deal not to run in the contest.

The Times has learnt that Mr Huhne, who entered Parliament at the last election, promised in a private meeting with Sir Menzies Campbell that he would not enter the race.

Mr Huhne, a former MEP who is barely known outside Westminster, promised to support Sir Menzies and sealed the deal with a handshake after a 50-minute meeting shortly after the resignation of Charles Kennedy. But barely one hour later Mr Huhne, a Treasury spokesman, returned to Sir Menzies’s office in the Commons to declare that he had changed his mind.

His decision not only dismayed Sir Menzies, 64, the party’s foreign affairs spokesman, but also caused uproar among the group of young modernising Lib Dem MPs who are seen as future leaders. They had agreed with Mr Huhne in November, when the first stirrings against Mr Kennedy’s leadership began to show, that none of them would run if Sir Menzies was a candidate.

The agreement was struck with Mr Huhne and his fellow pro-market “Orange Bookers” a clever, ambitious group ofMPs determined to return the party to the centre.

The group’s three standard bearers, Nick Clegg, 39, the deputy foreign affairs spokesman who is widely seen as a future leader, Ed Davey, 40, the party’s health spokesman, and David Laws, 40, the work and pension spokesman, all agreed with Mr Huhne that if Mr Kennedy stood down none of them would run, thus leaving the way clear for Sir Menzies, whom they would support.

They all knew that their own chances of winning the leadership would be better served after the next election when they would be better known.

After the resignation of Mr Kennedy last month, Mr Huhne agreed to attend the first campaign strategy meeting for Sir Menzies but failed to show up.

When the Orange Book MPs learnt that Mr Huhne had decided to run for the top job they were described as “seething”. But after hasty talks they agreed that they would stick to their word and remain committed to Sir Menzies even though their own dreams of the leadership could be at an end if Mr Huhne triumphed at the relatively young age of 51.

One senior Lib Dem MP said: “There was an understanding. Everyone understood it. By not running they would rally behind Campbell and it would give the Orange Bookers a chance to raise their profile and make a name.”

Mr Huhne, asked in an interview with The Times about the deal, replied: “It was tacit in some of the discussions that took place but it was never made explicit and I was never asked whether I was happy with that. What I did do however is formally offer my support to Ming before Christmas and I did say to him in the week when I was considering standing that if he wanted to hold me to that I would not stand and he kindly released me from that obligation.”

He added: “Other people thought there was a general understanding — it was, at most, tacit. There was no formal or informal deal.”

Mr Huhne has put green issues to the fore of his campaign, which has surprised many of his colleagues who had not heard him talk at length in public or private about the subject in the six years that he was an MEP.

An analysis by The Times of the 460 written questions Mr Huhne tabled to the European Commission between October 1999 and September 2004 revealed that fewer than 20 were about green issues.

One senior Lib Dem, who declined to be named, said: “Chris’s conversion to the green cause is a revelation to many of his colleagues.”

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