dereliction of our duty to the future of this country

Effectively pre-empting the outcome of the government's energy review due to be published in July, Mr Blair, in a speech to the CBI, said the issue of a new generation of stations was back on the agenda with a vengeance, alongside a big push on renewables and a step change in energy efficiency. Mr Blair's spokesman said the prime minister was speaking after reading "a first cut" of the Department of Trade and Industry-led review on Monday. He said the country could not rely on one new source to meet the coming energy gap, pointing out that renewable energy, such as wind and solar power, had technical problems.

In his speech last night Mr Blair said: "Essentially, the twin pressures of climate change and energy security are raising energy policy to the top of the agenda in the UK and around the world. "The facts are stark. By 2025, if current policy is unchanged there will be a dramatic gap on our targets to reduce CO2 emissions, we will become heavily dependent on gas and at the same time move from being 80% to 90% self-reliant in gas to 80% to 90% dependent on foreign imports, mostly from the Middle East, and Africa and Russia.

"These facts put the replacement of nuclear power stations, a big push on renewables and a step change on energy efficiency, engaging both business and consumers, back on the agenda with a vengeance. If we don't take these long-term decisions now we will be committing a serious dereliction of our duty to the future of this country." Although Mr Blair has warned before -in a speech to the CBI last November - that energy policy was back on the agenda with a vengeance, his remarks yesterday were significant since his considered judgment comes after viewing the initial findings of the energy review.

His aides said he was convinced that improved energy efficiency and renewables were not enough to fill the energy gap caused by the phasing out of the current set of ageing stations. His spokesman insisted: "There is no one club solution." Mr Blair has been heavily influenced by the government chief scientist, Sir David King, who believes nuclear power could in future provide 40% of electricity supply, double the current figure.

Mr Blair's move will open up divisions inside the cabinet, on the Labour backbenches and provide the first serious test of the nature of David Cameron's green credentials. The Liberal Democrats are firmly opposed to nuclear. Some environmentalists regard nuclear as a renewable option, and Mr Cameron's colleagues have been looking at making the investment climate more favourable to nuclear without actually endorsing new stations.

Mr Blair has also decided there will not be a separate white paper after the energy review, suggesting there will be no legislation to bring in nuclear stations - reducing the opportunities for a focused backbench rebellion in the Commons. He will face familiar questions on the cost and safe disposal of nuclear waste, and strong criticism from his own Sustainable Development Commission, chaired by Jonathon Porritt. The Nuclear Industry Association welcomed the prime minister's remarks, saying they came at a "crucial time".

Keith Parker, NIA chief executive, said: "Nuclear energy is a large-scale, low-carbon source of electricity generation that, as part of a diverse, balanced energy mix, can help to ensure security of energy supply." Resolutely anti-nuclear environmental groups were less enthusiastic. Greenpeace said Mr Blair's nuclear embrace was "recklessly incompetent".

Tony Juniper, head of Friends of the Earth, said: "This is not a chance comment it is a political set-piece. He's trying to soften the ground and get us all angrily running about in the hope that by the time the final report comes out in July we'll all be bored of arguing about it. We won't.

" Polls show that Mr Blair is pushing the right buttons to convince a traditionally equally split public on the issue of new reactors. A survey of 1,491 people this year, carried out by Mori and the Tyndall Centre for Climate Change Research, found 60% of people would support new atomic power stations as long as renewable energy sources were developed and used at the same time, and 63% agreed that Britain needed nuclear power as part of a mix of sources to ensure a reliable supply. But 74% said that nuclear power should not be considered as a solution for climate change before all other energy options had been explored.