Japan, as summit hosts, has made global warming a key priority at the G8 summit. Yasuo Fukuda told journalists that the G8 leaders "came to a mutual recognition" that it was necessary "to set ambitious midterm targets."

Although the agreement is seen as a step forward, it fell short of setting clear goals on emission cuts.

There was also criticism from environmental groups for the G8's failure to adopt clear and long-term targets. The WWF said in a statement "The G8 are responsible for 62% 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."

The UN will now take up the baton during climate change talks scheduled for December 2009 where a new framework agreement should be drawn up to replace the Kyoto Protocol due to expire in 2012.

A Russian delegation representative said Monday that G8 members had agreed on a long-term target of reducing emissions by 50%-90% by 2050, adding that Russia was ready to cut its energy output by 40% by 2020.

Alexander Bedritsky, the head of the Russian hydrometeorological service, said the agreement by developed countries would be reflected in the final document of the G8 Japan summit.

The majority of climate change experts, environmental groups and organizations say that global warming is caused by greenhouse gas emissions due to human activity, which is causing significant damage to the Earth, although a minority argue that the possible impact has not yet been proven.