TONY Blair's support for nuclear power suffered a blow yesterday when his own advisers condemned the technology, saying it was not the answer to tackling climate change.

Despite the Prime Minister's support for the nuclear industry, the Sustainable Development Commission (SDC) has come out firmly against the creation of a new generation of reactors. In its report, the commission said a new nuclear programme was not the answer to the problems of climate change or the security of supply.

The 15-strong commission said that even if Britain's existing nuclear capacity was doubled, it would produce only an 8 per cent cut in carbon dioxide emissions by 2035 and nothing before 2010.

And the report identified five 'major disadvantages' with nuclear power.

It highlighted the lack of a long-term solution to dealing with highly toxic nuclear waste. It also pointed out that the cost of nuclear power stations was highly uncertain and that there was a clear risk that the taxpayer would have to pick up the tab.

There was also a danger, said the report, that going down the nuclear route would lock Britain into a centralised distribution system for the next 50 years. The commission was concerned that a new nuclear power programme would undermine efforts to increase energy efficiency. It said the final disadvantage was the threat of terrorist attacks and radiation exposure if other countries with lower safety standards also opted for nuclear power.

The SDC said that on balance, these problems outweighed the advantages.

Chairman Sir Jonathon Porritt said: 'It is vital that we get to grips with the complexity of nuclear power.

'Far too often, the debate is highly polarised, with NGOs claiming to see no advantages to nuclear at all and the pro-nuclear lobby claiming that it's the only solution available to us.

'Instead of hurtling along to a prejudged conclusion (which many fear the Government is intent on doing) we must look to the evidence. There's little point in denying that nuclear power has benefits, but in our view, these are outweighed by serious disadvantages.

'The Government is going to have to stop looking for an easy fix to our climate change and energy crises there simply isn't one.' The SDC report said it was possible to meet Britain's energy needs without nuclear power.

If it pushed ahead with new low-carbon technology and continued working on energy efficiencies Britain could become a leader in the field, it said. This could give it an economic edge and meet the country's future energy needs at the same time.

Instead of sanctioning a new nuclear programme, the SDC urged Mr Blair to back an expansion of renewable power, new measures to promote energy efficiency and the development of technologies, such as 'carbon capture' to tackle the environmental threat posed by the burning of fossilfuels.

The commission's report comes just three months before the Government publishes the findings of its latest energy review, which is widely expected to clear the path for the new generation of nuclear power stations.

Existing nuclear stations generate about 20 per cent of Britain's electricity. All but one are scheduled to be closed by 2023.

Mr Blair provoked controversy last November when he announced a review of the prospect of a new generation of nuclear stations. His scientific adviser, Sir David King, is urging him to press ahead and Mr Blair is said to have been privately convinced.