Prime minister says need to diversify energy supply means replacing existing nuclear power plants will not be enough

Gordon Brown has said he has become “more ambitious” about nuclear power and that replacing existing capacity will not be enough in the light of rising oil prices.

When the government announced in January that it backed building new nuclear plants, it was understood to favour simply replacing ageing plants with new ones on the same sites.

Brown's new remarks suggest that plants on new sites may now be considered, and Downing Street has not ruled out this possibility.

Business secretary John Hutton has already said that no cap will be put on the amount of energy to be generated by nuclear power, which at present provides 20% of the UK's electricity.

Speaking to oil industry representatives at a meeting in Banchory, near Aberdeen, Brown said: “We want to do more to diversify our supply of energy and that is why I think we are pretty clear that we will have to do more than simply replace existing nuclear capability in Britain.

“We will be more ambitious for our plans for nuclear in the future.”

Firms including energy company E.ON and French firm EDF have announced that they want to build new nuclear plants in the UK, and the government has set a deadline of the autumn for applications.

The last new nuclear power plant to be built in the UK was Sizewell B, which opened in 1994.

Meanwhile, a £110m plan to build vaults for radioactive waste on site at Dounreay plant in Caithness is being pushed forward.

Dounreay Site Restoration has asked the Highland council to restart the planning application process for its proposal for storage vaults to hold low-level radioactive waste.

It had been held up by the Scottish Environment Protection Agency's request for an extension to consultation in 2006.

The cost of design, construction, operation and sealing of the vaults has been put at around £110m.