Britain’s target for reducing greenhouse gas emissions by the middle of the century is to be raised from 60 to 80 per cent.

Ed Miliband announced the increase today in his first major Commons statement since being appointed secretary of state for the newly created Department for Energy and Climate Change.

The 80 per cent target, which is to be written into the Climate Change Bill going through Parliament, brings the nation in line with demands by scientists and environmental lobby groups.

In accepting the recommendation made last week by the Climate Change Committee, which advises ministers on environmental policy, Mr Miliband told MPs that the need to tackle global warming is too important to be dropped or watered down even during tough economic conditions.

He recognised, however, that to reach the target, based on 1990 emissions, will require enormous investments across society to change Britain from a fossil fuel to a low-carbon economy.

Climate change campaigners greeted the announcement with widespread approval and described it as both ambitious and essential.

The increase maintains Britain’s position as a world leader in its legal and political commitment to reducing greenhouse gas emissions, including carbon dioxide.

But the commitment is widely regarded as workable only if the rest of the industrialised world signs up to similarly demanding reductions in carbon dioxide and other greenhouse gas emissions.

There is increasing unease amid an economic downturn that threatens to become a long-lasting recession that willingness to invest in green technology will falter in the face of high costs.

In his Commons statement, Mr Miliband acknowledged the high financial price of reducing emissions but said that the costs of doing little or nothing would be much higher in the long term.

“In tough economic times, some people will ask whether we should retreat from our climate change objectives,” he said. “In our view, it would be quite wrong to row back."

He added: “We all know that signing up to an 80 per cent target in 2050 when most of us will not be around is the easy part. The hard part is meeting it and meeting the milestones that will show we’re on track.”

Greg Clark, the Tory climate change spokesman, welcomed the 80 per cent target, saying: “The choice between aggressive and ambitious action on carbon reduction and a successful, powerful economy is, in fact, not a choice at all - they are one and the same.”

Lord Rees, president of the Royal Society, welcomed the target as courageous but highlighted widespread concerns about its feasibility when he said a failure to develop carbon capture and storage technology “will have severe consequences for meeting our emission targets and undermine the UK’s international leadership”.

Andy Atkins, the newly installed director of Friends of the Earth which campaigned for both the Climate Change Bill and the 80 per cent target, was “absolutely delighted” at the announcement.

He was concerned, however, that the Government remains intent on excluding the greenhouse gas emitted by the aviation and shipping industries from the carbon controls contained within the Climate Change Bill.

Dr Doug Parr, chief scientist for Greenpeace, recognised that to meet the target will require “hard choices will be made that will touch every Briton, but it can and must be done”.

The Energy Secretary announced several other measures alongside the 80 per cent target, including a promise to amend the Energy Bill to introduce feed-in tariffs to allow small scale energy producers - including homes with wind turbines or solar panels - to supply electricity to the National Grid at a guaranteed price.

He also pledged action to customers using pre-payment meters and those without mains gas being charged extra for their energy. Ofgem highlighted such charges last week as “unjustified”.

The feed-in decision should mollify 35 Labour backbenchers who in April rebelled against the government on the issue.

Times recommends

• Energy-saving ideas from switched-on professor
• Rooks are as clever with tools as chimpanzees
• Burping of the lambs blows roast off menu