It would be foolhardy for the Government to rely excessively on one technology to produce electricity, a Department of Energy spokesman has said.
He was replying to a call by the pressure group Supporters of Nuclear Energy (SONE) for nuclear to be at the forefront of electricity supply policy.
The spokesman said: "Cost effectiveness is already at the heart of our energy policy. New nuclear is low carbon, secure and affordable. It will be important, but only as part of a mix alongside a portfolio of other technologies.
"In maintaining energy security while cutting damaging carbon emissions, it would be foolhardy for us to pick and rely excessively on one technology.
"We're reforming the electricity market to give all forms of low carbon generation - new nuclear, renewables and carbon capture and storage - the opportunity to compete over the coming decades."
He went on: "For householders we expect the costs of our policies to be more than offset by the steps we're taking to save on consumption through greater energy efficiency.
"And we want energy intensive industries to have a long-term viable future in the UK, which is why we'll shortly announce a package of measures for those industries whose international competitiveness is most affected by our energy and climate change policies."
He was responding to a letter sent to the Chancellor, George Osborne, by Sir William McAlpine, chairman of SONE, describing the Government's energy policy as an imposition on consumers and industry and as failing in its objectives.
Sir William: "We welcome your determination that Britain should not impose costs on consumers and industry that exceed those of our competitors in an effort to reduce carbon emissions and your reduction of some subsidies.
"We do so because we regard current energy policy as an imposition on both consumers and industry and commerce. More importantly, it does not give value for money. In fact, it is failing in all its objectives - security (which renewables generally can never provide) of low carbon supply at affordable cost."