�A former Lib Dem Belsize councillor who used to be a Labour Party member has jumped ship again to stand as a Green councillor in the Highgate by-election.

Alexis Rowell served as a Lib Dem councillor on Camden Council from 2006 to 2010 and was the borough’s “eco-champion”.

He defected to the Green Party this week – announcing that he planned to stand in the Highgate by-election on September 14.

After his selection on Tuesday night, Mr Rowell said: “I have been growing increasingly disillusioned with the Lib Dems since the party joined the coalition government.

“My principal reason for leaving was Chris Huhne’s support for nuclear power.

“But I have also been completely unimpressed with the coalition’s overall environmental record and appalled by what their policies and cuts are doing to the social fabric.”

Mr Rowell formally resigned from the Lib Dems on Monday night after penning a resignation letter to Deputy Prime Minister Nick Clegg.

In his letter, he spoke of his “shock” that Mr Clegg had signed the foreword to the bill to privatise the NHS.

He also cited as his reason for leaving the “draconian front-loaded” cuts to local government, the free schools policy, the “virtual abandonment of state-funded” higher education, the lack of any action on banker bonuses and a host of other free market or libertarian policies which he did not vote for.

But Cllr Keith Moffitt, the leader of Camden Council when the Lib Dems and Tories were in coalition from 2006 to 2010 and who is still leader, claimed that Mr Rowell had a habit of jumping ship when a political parties had to make tough decisions.

He said: “To Alexis Rowell’s former colleagues in Labour and the Lib Dems, this news will sadly come as no surprise.

“Alexis started his political journey in the Labour party and never found it easy working with parties making difficult decisions – whether that was locally or nationally.”

The by-election was called when Labour councillor Michael Nicolaides stepped down after 18 months in the job because of other commitments. The last time the ward was fought, in May 2010, the Greens won one seat and Labour won two.

Mr Rowell was a BBC journalist from 1990 to 1998. He currently runs a climate change and peak oil consultancy and helps to co-ordinate local environmental group Transition Belsize.