G8 nations, papering over deep differences, said today they would work toward a target of at least halving global greenhouse gas emissions by 2050 but emphasised they would not be able to do it alone.
In a communique released during a summit in northern Japan, the Group of Eight leaders agreed that they would need to set interim goals on the way to a "shared vision" for 2050 although it gave no numerical targets.
Mention of mid-term goals was an advance from last year when the G8 agreed only to "seriously consider" a goal of halving emissions by mid-century.
But calling on countries involved in UN negotiations on climate change to also "consider and adopt" the 2050 goal satisfies the United States, which has said it cannot agree to binding targets unless big polluters such as China and India rein in their emissions too.
Dan Price, assistant to the president for international economic affairs, described the G8 declaration on climate change as "an excellent discussion, and an excellent declaration" and he said that "significant progress" was made.
Price said the statement reflected that "the G8 alone cannot effectively address climate change, cannot effectively achieve this goal, but that contributions from all major economies are required".
Critics outside the rich nations' club slammed the deal. Environmental campaign group WWF said the leaders had ducked their responsibilities.
"The G8 are responsible for 62 per cent of the carbon dioxide accumulated in the Earth's atmosphere, which makes them the main culprit of climate change and the biggest part of the problem," WWF said shortly after the statement was issued.
"WWF finds it pathetic that they still duck their historic responsibility," the campaign group said in a statement.
The European Union and Japan had been pressing for this year's summit to go beyond just "considering" the 2050 goal, and Brussels had wanted clear interim targets as well.
South African Environment Minister Marthinus van Schalkwyk said he feared this year's communique was a step backward.
"While the statement may appear as a movement forward, we are concerned that it may, in effect, be a regression from what is required to make a meaningful contribution to meeting the challenges of climate change," van Schalkwyk said.
The UN-led talks aim to create a new framework for when the Kyoto Protocol expires in 2012 and are set to conclude in Copenhagen in December 2009.
The G8 comprises Japan, Britain, Canada, Germany, France, Italy, Russia and the United States.