The US new proposal , which came an hour before midnight yesterday, would eliminate language that called upon developed nations to consider specific, internationally binding, quantified reduction commitments, replacing it with text that calls upon countries to adopt any measures they deem appropriate, WWF said in a press release.

"At the eleventh hour, the US has submitted a proposal that is the equivalent of taking no action at all against climate change," WWF International Director General James P Leape said. "This proposal would gut the international effort towards halting climate change and put the future of our planet at risk."

"The Bush administration has a moral obligation to make commitments that are commensurate with their contribution to the climate crisis," said WWF Global Climate Change Director Hans Verolme. "The US government, aided by a small group of nations including Canada and Japan, has over the last few days thrown up several roadblocks in the negotiations," he said.

He added: "We are pleased that several large emerging economies, including China, Brazil, and South Africa, are still showing flexibility and creativity in their contributions to the Bali negotiations. That is the same spirit one would hope we could expect from the US."

"With these actions, the US jeopardizes the agreements that have already been reached on deforestation, technology and adaptation," he noted.

Yesterday evening, Al gore, Nobel Peace Prize co-laureate and former US vice president, in a speech delivered here, also accused his own country, the United States, of being "principally responsible" for blocking progress here toward an agreement on launching negotiations to replace the Kyoto Protocol when it expires in 2012.

WWF, a global environmental conservation organization, said more than 50 members of the US Congress from both parties wrote to US President George W. Bush urging him to shift gears and play a constructive role in bringing these negotiations to a productive close.

The Bali UN climate conference, which is due to end today, came to a deadlock as the EU and the United States, Japan, Canada have disputed over a number of goals in emissions in the final text for the Bali Roadmap, which will guide negotiations on a new global climate deal before the Kyoto Protocol when expires in 2012.

The EU favored a 25-40 percent deep emissions cut for rich countries by 2020, while the United States said such a range would prejudge the outcome of the negotiations.