Labour has the strongest policies to protect nature and combat climate change, a Friends of the Earth (FoE) survey suggests.
Its election pledges narrowly beat the Green Party and the Liberal Democrats – with the Conservatives far behind.
One key climate policy area is aviation, and Labour has now announced plans for a levy on people who take frequent flights.
The FoE league table marks the parties on 45 policy points.
Its scores are:
FoE spokesman Dave Timms said: “Environmental issues have been given greater priority in this election than ever before – and with the world in the midst of an ecological and climate crisis this must be the next government’s top priority.
“Many of the policies that Labour, the Liberal Democrats and Green Party have put forward are commensurate with, or striving to meet, the challenges we face.
“It is disappointing we have not seen the same urgency, ambition or consistency from the Conservative Party.”
The result will be a shock to the Green Party, whose overriding concern is protecting the planet and who typically top the environment policy charts by a wide margin.
The Greens complained the scoring should only have included commitments made in manifestos.
But in a bid for the youth vote, Labour has challenged the Greens by devoting the top section of its manifesto to tackling the environment crisis.
One high-scoring policy in the FoE survey is on aviation. Labour has been under pressure from trades unions to safeguard jobs in the industry.
But after correspondence with Friends of the Earth, the party strengthened its position by backing a frequent flyer levy on the 15% of people who take 70% of flights.
A letter to the group from four Labour shadow cabinet ministers also promised to review its Aviation National Policy Statement against much tougher carbon targets.
What about Heathrow?
Labour said expansion at Heathrow would be cancelled if it was not consistent with climate targets.
A Labour government would also divert funds from the roads programme for public transport, the party says.
The Greens did not provide any more clarification or policies to strengthen their manifesto.
Mr Timms said: “Labour’s manifesto contains strong, funded policies on home energy efficiency and renewables. This was boosted by significant additional pledges during the campaign on plans for tree planting, food policy, public transport and cycling.
“The Lib Dems and Greens both scored well, and had policies roughly commensurate with the scale of the crisis.”
He added: “The Conservatives have some good policies – especially on agriculture – but in sector after sector its commitments were invariably weaker than the other parties’, entirely absent or just plain bad.”
The Conservatives are committed to a £28.8bn road-building programme that experts say is not compatible with carbon targets because, even if the cars of the future are electric, gathering the resources to make the cars will still generate emissions.
The Tories said their climate targets were world-leading but road congestion had to be tackled.
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