All three of the major political parties are falling short in their response to the threats facing the environment, according to a study released today.

A group of leading environmental organisations assessed the green credentials of the Tories, Labour and the Liberal Democrats and found them all wanting.

The report praised David Cameron, the Conservative leader, for raising the profile of green issues, but found a "stark" gap between the rhetoric of his party and its policy commitments on the environment since the 2005 election.

Labour was commended for displaying international leadership on climate change, but was criticised for failing to meets its renewable energy targets, stop rising greenhouse gas emissions in the UK and implement a marine bill.

The Lib Dems scored best in the series of tests, with an "ambitious" set of actions to tackle climate change, but the report raised "serious concerns" about the party's policies on the natural world and planning.

The Green Standard assessment was carried out by the Green Alliance, RSPB, Friends of the Earth, the Woodland Trust, WWF, the Wildlife Trusts, the National Trust, the Campaign to Protect Rural England and Greenpeace.

Stephen Hale, director of Green Alliance, said: "It is very disappointing that none of the three main parties are yet providing the leadership and action we need.

"The environmental ambitions of the parties are very welcome, but all three must close the gap between rhetoric and delivery in the run-up to the next general election."

The parties were assessed on domestic action on climate change, international action on climate change, enabling "green living", the natural environment, planning and environmental taxes and subsidies.

They were awarded a green, amber or red light in each area - with the top grade awarded for both ambition and commitment to green policies, amber for a mixed picture, and red to show concern for a party's approach to the area and lack of positive commitment.

The government's attempts to reform the tax system in line with environmental costs and to tackle climate change at home were described as "timid", but it was awarded a green light for international action on the issue.

However, Labour got a red light for planning, because of its heavy focus on economic development and not sustainability.

While the climate change bill would make the UK the first country in the world to have a legal framework for transferring to a low-carbon economy, today's report warned that plans for airport expansion, road building and new coal-fired power stations were undermining progress.

The Conservatives were given two red lights by the organisations, for international action on climate change and green living, and no green lights.

The assessment did say that the party, which is due to publish the findings of its quality of life policy review including green issues tomorrow, was instrumental in getting the government to introduce the climate change bill.

The authors recognised that the Conservatives had not published their commitments yet but warned that there may be serious clashes between its environmental plans and other areas of policy such as the competitiveness commission, which called for wide-ranging tax cuts.

It concluded that the party would need greater substance on environmental issues.

The Lib Dems were awarded a green light for their commitment to domestic attempts to tackle climate change, but the report acknowledged that the slim chance of them forming a government allowed them greater freedom to develop policies.

The party is currently considering a target of achieving a carbon-neutral economy by 2050, having already adopted a policy of a minimum 60% reduction in carbon emissions by then.

The Lib Dems also got the top rating for their green living plans and for the environmental tax category for their commitment to the "green tax switch", to shift the burden from income to polluting behaviour.

But they got a red light for their approach to the natural environment, and the report warned that all three parties were failing to give enough attention to policies to protect UK countryside and wildlife.

The Lib Dems said they continued to set the green standard the other parties needed to meet.

The party's environment spokesman, Chris Huhne, said: "We are three times as green as the Labour party, and streets ahead of the Tories.

"The Liberal Democrats have an ambitious and realistic objective for a zero-carbon Britain, tackling carbon emissions from every part of the economy: transport, housing, offices and factories."

A Labour party spokesman said: "We welcome a healthy debate with the green groups and though we do not agree with their assessment in all respects we welcome their recognition of the progress we are making.

"The key difference between Labour in government and the other parties is that we are getting on and delivering while the other parties only have to make promises."

A Tory spokesman said: "The time to judge the Conservative party's ideas on the environment is after they have been announced, not before.



"Tomorrow the quality of life group, set up by David Cameron, will unveil incredibly ambitious and comprehensive set of proposals to tackle the challenge facing our environment."