Ken Livingstone is “greener” than his rival to be London Mayor Boris Johnson when it comes to policies, according to a new report commissioned by Friends of the Earth and Greenpeace.

On the eve of the London Mayoral election, the campaign groups released the research which rated four of the candidates for the role: Tory Boris Johnson, Green Party candidate Jenny Jones, Labour’s Ken Livingstone and the Lib Dems’ Brian Paddick.

Understandably, Ms Jones came top of the table, with Labourite Livingstone taking second place – and the incumbent Mayor Mr Johnson languishing in the last spot.

The report said the Green Party contender consistently ranks first or second in the research categories, which covered: air pollution, transport, aviation, climate change, energy and energy efficiency and green spaces.

Ken Livingstone snatched first place in the energy category though, with campaigners impressed by his “radical” plans for a London energy co-operative and “innovative” efficiency initiatives while in office. In contrast Johnson came fourth in the category for being “unambitious on energy”, with FOE and Greenpeace worried by his failure to support the decarbonising of the electricity supply in line with Committee on Climate Change advice.

Dr Doug Parr, Greenpeace’s Chief Scientist said: “This analysis reveals real differences between the leading London mayoral candidates on the quality of their policies and record of delivery.

“People look to world cities like London to provide political leadership on national and international problems like ending our oil and gas addiction, so temporarily sticking air pollution to roads and championing airport growth and cars won’t cut it.”

He added: “Policies to insulate the city’s draughty homes, make public transport more appealing and cycling safer can have a serious impact on carbon emissions and Londoners’ wallets and wellbeing.”

Voting in the London Mayoral election takes place today (3 May).