United Nations Secretary-General Kofi Annan has urged Russia to salvage the Kyoto protocol, calling the pact a first step in a decades-long endeavour to combat global warming.
"I encourage all remaining (developed) countries that have not joined in this crucial global endeavour to expedite the ratification process," Annan said in a written statement on Wednesday to a 180-nation conference attended by environment ministers.
He cited growing concern about rising sea level rises, crop failures and heat waves linked to emissions of greenhouse gases.
The 1997 Kyoto Protocol cannot enter into force without backing from Russia after President George W. Bush pulled the United States, the world's biggest polluter, out in 2001. Bush says Kyoto is fatally flawed.
To take effect, Kyoto must be accepted by nations responsible for 55 percent of emissions of carbon dioxide in rich states. It has reached 44 percent and needs Russia's 17 percent after the United States pulled out its 36 percent share.