The move came against the grain of intense industry lobbying to dilute an ambitious European Union climate change program, including tough carbon caps, at a meeting of EU leaders on Thursday.

Business lobby groups argue that cutting carbon emissions will add to fuel bills, but Miliband said the costs of not fighting climate change were greater, and would detail next year how Britain would embark on meeting the goal.

"In tough economic times, some people will ask whether we should retreat from our climate change objectives," he told Britain's Parliament.

"In our view, it would be quite wrong to row (pull) back."

EU leaders Thursday reaffirmed a December deadline to agree EU-wide energy and climate proposals, and stick to a target to cut greenhouse gas emissions by a fifth by 2020, at a summit overshadowed by the threat of a punishing recession.

But the leaders handed concessions to some heavy industry and coal-dependent former communist countries.

Recruited to the newly-created energy and climate change ministry two weeks ago, Miliband said the government would make the new UK target binding by amending its Climate Change Bill, going through Parliament, and won approval from green groups.

"In a decade in power Labor has never adopted a target so ambitious, far-reaching and internationally significant as this," said Greenpeace chief scientist Dr Doug Parr.

Miliband also said he would amend a new UK energy law being debated to introduce 'feed in' tariffs for small-scale renewable energy generation. He did not specify which technologies.

Feed-in tariffs pay people a premium to generate "green" electricity and feed this back into the national grid, earning them a profit which helps to pay for installing solar panels, wind turbines, groundwater heating systems and other sources.

The measure could be a big boost to installers of such renewable power, such as Centrica's British Gas arm.

"The provision of a feed in tariff is crucial to the success of microgeneration technologies, which have a key role to play in meeting the government's renewable energy and carbon emissions targets," said Gearoid Lane, managing director of British Gas New Energy.

Miliband said he would make a separate announcement on boosting renewable heat.

Britain's chief adviser on climate change, Adair Turner, last week recommended the more ambitious 2050 goal, which is an 80 percent cut compared to 1990 levels.

The new emissions target would apply to all six greenhouse gases defined under the United Nation's Kyoto Protocol, not just carbon dioxide as formerly.

Miliband said he would also discuss new legislation to end unfair pricing on pre-payment meters, unless energy companies can show they will stop over-charging customers.