"The document as it stands now does not command consensus," Russian chief negotiator Alexander Bedritsky told the 189-nation meeting during a marathon session stretching into the early hours.

Russia proposed that any agreement should allow all nations, not just the wealthy industrial countries, to be able to offer voluntary commitments in reducing greenhouse gases.

Kyoto in its first phase does not include the developing world or big, and rapidly growing, polluters such as India and China and a major theme of the Montreal talks is how to bring them on board.

Other ministers praised Russia for bringing Kyoto to life - its "Yes" enabled Kyoto to enter into force in February 2005 after years of delays - but urged Moscow to back off.

"If it were not for Russia, the Kyoto Protocol would not be in force," British Environment Minister Margaret Beckett told weary delegates, adding that Moscow deserved a place of honor

But she said this was not the time to scuttle the historic talks. "It would be a tragedy if a further decision by the Russian Federation would block more progress."

Pressure on Russia came from all sides.

"We have the opportunity to keep (Kyoto) alive and kicking if we adopt this (decision) tonight," European Union Commissioner Stavros Dimas said, calling climate change the "largest threat we face in our times."

Under Kyoto, about 40 industrialized nations have to cut emissions of heat-trapping gases. The United States, the biggest emitter, pulled out of Kyoto in 2001, denouncing it as an economic straitjacket.

Most scientists say that a buildup of greenhouse gases could trigger catastrophic changes, with more powerful storms, floods, desertification and rising world sea levels.

AS SOON AS POSSIBLE

The draft decision would urge rich nations to decide new commitments beyond 2012 as early as possible without setting a detailed timetable.

Earlier, the talks had been nearing a breakthrough after the United States agreed to a Canadian plan for nations to join an open-ended "dialogue" about combating climate change under the United Nations' 1992 Framework Convention on Climate Change.

"Basically, there is an agreement," US negotiator Harlan Watson told Reuters.

The two-week negotiations in Montreal have followed a twin track, one pursuing talks to advance Kyoto and a broader dialogue under the UN Climate Convention, Kyoto's parent treaty.

The plan by host Canada for international talks calls for an open-ended "dialogue ... to explore and analyze strategic approaches for long-term cooperative action to address climate change."

After pressure from Washington, Canada watered down suggestions that the dialogue was a prelude to Kyoto-style emissions targets opposed by Washington.

Poor countries have no targets under Kyoto and say that rich industrial states have to take the lead in cutting emissions after fueling their economies with coal, oil and gas since the Industrial Revolution.

Global warming is widely blamed on a build-up of gases from burning fossil fuels in power plants, autos and factories.

Under Kyoto, about 40 industrialized nations have to cut their emissions by an average of 5.2 percent below 1990 levels by 2008-12.