The proposal's reference to a potential treaty's legal form and post-2020 timeframe are "very, very vague" and show a "clear collusion" of China, the U.S. and India, Conrad said in an interview today.

A U.S. spokeswoman declined to comment on the proposal. India's lead negotiator, J.M. Mauskar, said in an interview: "It is wrong to say India is inflexible." He declined to comment further. China's negotiator Xie Zhenhua says the top priority of the Durban talks is extending Kyoto, according to Xinhua News Agency.

Xie said China has a "flexible and open attitude to discuss a process for post-2020 arrangements acceptable to all parties," Xinhua reported. China's press office didn't immediately respond to a Bloomberg News request for comment.

Road Map

The EU says it won't commit to new Kyoto targets after 2012 without agreement on a road map pointing toward a new treaty that would bind all nations. That would require support from China and India, which had no goals under Kyoto. The EU yesterday won support from its plan from 120 nations including islands in the Pacific Ocean and the poorest countries.

The U.S., which never ratified Kyoto, says it won't agree to start negotiating a new treaty at this time because China, India and other big developing economies aren't willing to take on legally binding commitments.

The dispute may poison the talks enough that negotiations collapse, said Alden Meyer, who has been following global environment meetings for more than two decades for the Union of Concerned Scientists.

"If you have a breakdown of trust, what will the political ramifications of that be?" Meyer said in an interview. "There will be extreme anger from a broader range of developing countries that developed countries are backing out of the legally binding framework. What will the reaction be to that anger? Will they bring down the whole house of cards? We don't know. Stay tuned."

Rising Pollution

Greenhouse gases hit a record last year, and scientists at the conference warned that current pledges leave the world on course for the biggest temperature increases by 2100 since the last ice age ended. Developing nations said they're upset the industrial nations haven't already extended Kyoto pledges.

"The climate change effects we're experiencing in Lesotho and other countries are a matter of life or death because we don't have the safety nets that the developed world has," Manete Ramaili, the southern African nation's environment minister, said in an interview. "We have to have binding targets. It's a must."