An official report has admitted that the government will fall short of its ambitious target for cutting Britain's carbon dioxide emissions.
The long-awaited publication of the climate change programme review revealed that, despite an "ambitious" range of new measures, strong economic growth has left the government off-track.
Tuesday's news will prove embarrassing for Tony Blair, who is highlighting the issue during a visit to New Zealand.
The prime minister also sought to make global warming a key plank of last year's UK G8 presidency.
Ministers have been aiming to cut emissions by 20 per cent from 1990 levels by 2010.
But the review confirmed that the likely reduction will now be 15 to 18 per cent.
If the reduction falls at the lower end of that forecast, or slips further below it, the UK could also miss the less ambitious Kyoto target of a 12.5 per cent cut by 2010.
Since 1997 emissions of CO2 have risen by 1.9 per cent, leaving the country just 5.6 per cent below the 1990 position.
The Conservatives said the review was a "grim admission of failure".
And the Liberal Democrats said it revealed "an appalling record" on tackling global warming.
Action plan
Setting out a range of further action to reduce CO2 emissions, the review backed a stricter emissions cap for industry and measures to encourage the use of biofuels in petrol.
It also urged tighter building regulations and measures to improve household energy efficiency.
There was also an acknowledgment that the public, businesses and public authorities will also have to take action if the government's targets are to be achieved.
"This ambitious programme sets out our plans for tackling climate change at global, national and individual level," said environment secretary Margaret Beckett.
"All three are essential. Climate change is a global problem that needs global solutions.
"But we must act now to meet our commitments. This programme contains a package of far-reaching measures that will affect all the major sectors and sources of UK emissions.
"But it is not the last word. There is more that government can and will do to meet the target.
"Further contributions could be made by the energy review, a review of measures to improve the sustainability of existing building and other policies over the coming years."
Failures
Shadow environment secretary Peter Ainsworth described the review as "a grim admission of failure on what was meant to be one of Mr Blair's top priorities".
"Worse still, it fails to chart a course which will get us back on track," he added.#
"The government's efforts to tackle climate change remain piecemeal, timid and half-hearted.
"This was an opportunity for Labour to show how they intend to lead the world, and they have missed it."
The Conservatives called for a clear explanation of UK emissions modeling, a long-term framework with annual reduction targets and action to tackle pollution from international aviation.
And Lib Dem environment spokesman Chris Huhne said: "The government has failed to meet the goals it set itself, and is also failing by comparison with more enlightened foreign governments.
"Even the modest progress made on the Kyoto basket of greenhouse gases is largely an accidental result of the switch from coal to gas powered electricity generation, and has nothing to do with government policy.
"This is an appalling record. The steady rise in carbon emissions since 2000 when the government capitulated to the fuel protesters is now coming home to roost.
"Green taxes have been falling in real terms since then with the predictable results that we see today."
