Dec. 17 (Bloomberg) -- The U.S. and China, the world's two biggest emitters of greenhouse gases blamed for climate change, have two years to resolve differences blocking a new agreement to help slow the planet's warming.

After two weeks of talks concluding with three sleepless nights for negotiators, a scolding from UN Secretary-General Ban Ki-Moon, and public tears from the conference head, the 187 nations meeting on Bali in Indonesia agreed on a document setting a 2009 deadline for a new treaty to limit gas emissions. The existing accord, the Kyoto Protocol, runs out in 2012.

The Bali meeting made clear that for a new pact to emerge, the U.S. will have to persuade China and India to do more to curb pollution and overcome fear that doing so will hurt economic growth, participants said. Meanwhile, the European Union and developing nations say the U.S. must accept mandatory emissions cuts to avoid dangerous climate shifts, such as the flooding of island states and coastal cities from melting ice. Without these concessions, scientists say reducing worldwide emissions by half by 2050 won't happen.

``These talks came to the brink of collapse,'' Alden Meyer, a Washington lobbyist for the Cambridge, Massachusetts-based Union of Concerned Scientists, said in an interview at the Bali meeting. ``Now the hard work begins to get meaningful commitments from my country on the table and doing our responsible share in dealing with this urgent problem.''

Closed Door Meetings

Country delegates, meeting behind closed doors, sometimes in formal talks, sometimes in small groups, hammered out the agenda that will guide United Nations-sponsored climate negotiations for the next two years. The U.S. succeeded in diluting language that would require specific mandatory cuts in emissions. China, India and 130 developing countries resisted calls for them to limit pollution as their economies expand.

``This doesn't really define at this stage the nature of action to be taken by any country,'' Elliot Diringer, director of International Strategies at the Pew Center on Global Climate Change, said of the agreement in an interview from Bali.

The accord came on Saturday afternoon, after talks were extended by a day and negotiations had gone through Friday night. James Connaughton, chief environmental adviser to U.S. President George W. Bush, said he got 2 1/2 hours sleep in three days. Yvo De Boer, who oversaw the talks as executive secretary of the UN Framework Convention on Climate Change, said he hadn't slept in two days.

De Boer had left the auditorium in tears after China's delegation demanded to know why the session had twice been started while separate talks were ongoing elsewhere. The consensus finally was reached after Ban flew back to Bali and warned negotiators that a failure of talks would amount to ``a betrayal of our planet.''

Cheers and Criticism

The speeches by Ban and Indonesian President Susilo Bambang Yudhoyono ``electrified the room, and almost by electrolysis, any resistance that was there just disappeared,'' de Boer said.

While delegates greeted the consensus with cheers, neither the U.S. nor China was pleased with the agreement. China's deputy head of delegation Su Wei called it ``weak,'' while White House spokeswoman Dana Perino said the Bush administration had ``serious concerns'' about it.

Bush rejected the existing Kyoto climate treaty in 2001, arguing that mandatory emissions cuts would hurt the economy. He and many U.S. lawmakers at the time also objected to the accord because it doesn't require rapidly developing economies such as China to curb their greenhouse-gas emissions.

``Empirical studies on emission trends in the major developing economies now conclusively establish that emissions reductions principally by the developed world will be insufficient to confront the global problem effectively,'' Perino said in a Dec. 15 statement.

China and India

China and India together might account for 56 percent of emissions growth as populations attempt to mirror Western lifestyles, the International Energy Agency said last month. China's emissions, largely driven by coal burning, will probably more than double to 11.4 billion tons by 2030, unless lawmakers change energy policies, the IEA said.

Still, China's per capita emissions will be less than half those in the U.S., at 7.9 tons versus 19 tons, the report said. The EU and the U.S. caused the build-up of the world's emissions, accounting for more than half of cumulative gas output from 1900 to 2005. China and India contributed 8 percent and 2 percent, respectively, the IEA said.

The European Union, China and developing nations including India and Pakistan had lobbied for the final document to require industrialized nations to reduce emissions by between 25 and 40 percent by 2020 from 1990 levels, language rejected by the U.S. In the end, the goals were included in a footnote to the agenda.

Forest Plan

Emissions reduction isn't the only issue to be resolved by 2009. Countries will have to agree on ways to reward developing nations for preserving forests. Communities in regions like Brazil, the largest rainforest nation, and Central Africa, which ranks second, may get voluntary funds or tradable credits for keeping trees, which absorb carbon dioxide as they grow.

Clearing forests accounts for about 20 percent of the carbon dioxide emissions globally. The issue wasn't dealt with in the existing Kyoto Protocol.

Negotiators in the next two years also will have to decide on the system to fund the transfer of clean-energy technologies such as wind power to allow developing nations to grow with limited pollution. The financing from richer nations may include funds to buy intellectual property rights, which poor countries can't afford on their own, according to the Bali document.

To contact the reporters on this story: Kim Chipman in Nusa Dua, Indonesia, at kchipman@bloomberg.net; Leony Aurora in Jakarta at laurora@bloomberg.net

Last Updated: December 17, 2007 00:04 EST