Gordon Brown said yesterday that the IPCC's "measured" report underlined the urgent need for global action to tackle the scourge of climate change.
The Prime Minister (below) greeted the publication of the report showing that the Earth is heading for a warmer age at a quickening pace by announcing that he wanted to introduce bigger long-term cuts in carbon emissions than had been previously planned.
Mr Brown will set out in the next few days various ways in which he believes emissions can be cut.
But he confirmed that he will be asking the Government's own environmental experts to consider whether the UK's existing targets for reducing carbon emissions can be extended.
He will also use the forthcoming United Nations climate conference in Bali to push for more binding international targets, which place the heaviest burden on developed countries.
But environmental campaigners and opposition politicians claimed the Prime Minister would have to reconsider his own policies in the light of the warnings in the report.
Greenpeace spokesman Ben Stewart said the IPCC's "clarion call for action" should be ringing alarm bells in Downing Street. He added: "When Gordon Brown reads it, he should immediately drop plans for new runways and new coal-fired power stations in this country.
"We simply can't go on belching out carbon like we have done. That's what the scientists are telling us."
Conservative environment spokesman Peter Ainsworth said: "This is a very disturbing report which shows the need for urgent and international action to tackle climate change."
For the Liberal Democrats, Chris Huhne said that the report emphasised the demand for action at Bali. He said: "The industrial countries have to take the lead because they are responsible for 70 per cent of the carbon that has been emitted, and every extra ounce of carbon has a life of 100 years in the atmosphere."
To have your say on this or any other issue visit www.independent.co.uk/IoSblogsReuse content