Prime Minister Tony Blair has sought to champion tackling climate change, particularly under Britain’s presidency this year of the Group of Eight economic powers.
At a July summit, G8 nations agreed on measures to tackle global warming but set no targets, mainly due to resistance from the United States which rejects the Kyoto Protocol on curbing greenhouse gas emissions.
Scientists predict global warming will put millions of lives at risk through rising sea levels, floods and droughts.
"It is difficult to criticise other countries, such as the United States, who will not meet their (Kyoto) targets if we are unable to meet our commitments," said Lord May, president of the Royal Society, the British national academy of science.
He said the government risked missing its Kyoto commitment to cut greenhouse gas emissions by 12.5 percent from 1990 levels by 2012.
"Emissions have risen for the last two years and if this trend persists, the UK will miss its Kyoto target," said May.
He pointed out that emissions in the United States had actually declined in the last two years, although they were still 20 percent above 1990 levels.
May told the House of Lords there was a "disconnect" between the two central themes of Britain’s G8 presidency.
"On the one hand are solemn and sincere promises to increase aid and support development to Africa: on the other hand, there is a lack of agreement on measures to curb greenhouse gas emissions which means increasing amounts of aid will be spent on tackling the consequences," he said.
May’s attack comes before a meeting later this month of 150 countries in Montreal to discuss taking the Kyoto Protocol beyond 2012 when the first phase ends.
He said Britain needed more regulations to encourage the private sector to invest more in renewable energy sources.