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Two weeks of international climate talks marked by bitter disagreements and angry accusations culminated Saturday in a last-minute U.S. compromise and an agreement to adopt a blueprint for fighting global warming by 2009. Now comes the hard part.

Delegates from nearly 190 nations must fix goals for industrialized nations to cut their greenhouse gas emissions while helping developing countries cut their own emissions and adapt to rising temperatures.

Negotiators also will consider ways to encourage developing countries to protect their rapidly dwindling forests — which absorb carbon dioxide.

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But it was a separate issue that precipitated a riveting, final-hour floor fight.

India sought to amend the document to strengthen requirements for richer nations to help poorer with technology to limit emissions and adapt to climate change's impacts.

The head of the U.S. delegation, Undersecretary of State Paula J. Dobriansky objected, setting off loud, long boos in the hall.

Next, delegate after delegate took aim at the United States, with South Africa saying Dobriansky's intervention was "most unwelcome and without any basis," and Uganda saying "We would like to beg them" to relent.

Then the delegate from Papua New Guinea leaned into his microphone.

"We seek your leadership," Kevin Conrad told the Americans. "But if for some reason you are not willing to lead, leave it to the rest of us. Please get out of the way."

The U.N. climate conference exploded with applause, the U.S. delegation backed down, and the way was cleared Saturday for adoption of the "Bali Roadmap."

"This is the beginning, not the end," U.N. Secretary-General Ban Ki-moon told The Associated Press following the contentious climate conference, which stretched into an extra day. "We will have to engage in more complex, long and difficult negotiations."

Those gathering on the resort island of Bali were charged with launching negotiations to replace the Kyoto Protocol, which expires in 2012. What they decide in the next two years will help determine how much the world warms in the decades to come.

In a series of pivotal reports this year, a U.N. network of climate and other scientists warned of severe consequences — from rising seas, droughts, severe weather, species extinction and other effects — without sharp cutbacks in emissions of the industrial, transportation and agricultural gases blamed for global warming.

To avoid the worst, the Nobel Prize-winning Intergovernmental Panel on Climate Change said, emissions should be reduced by 25 percent to 40 percent below 1990 levels by 2020. Greenhouse and other heat-trapping gases should be reduced at least by half by 2050, they added.

Despite an aggressive EU-led campaign to include specific emissions reduction targets for industrial nations — using the figures and time table above — the final roadmap has none.

The guidelines were eliminated after the U.S., joined by Japan and others, argued that targets should come at the end of the two-year negotiations, not the start.

When talks begin, the focus again will fall on the United States, the only major industrial country that did not accept Kyoto. That pact requires 37 industrial nations to reduce greenhouse gases by a relatively modest 5 percent on average in the next five years.

A turning point may come a year down the road following the U.S. election of a new president, who many environmentalists hope will support deeper, mandatory emissions cuts in contrast to President Bush, who favors only voluntary approaches to reining in greenhouse gases.

The exemption of developing nations from the Kyoto Protocol's mandatory caps has also long been a key complaint of American opponents to the U.N. climate treaty process.

White House press secretary Dana Perino said the U.S. welcomed the positive steps outlined in the roadmap but had "serious concerns" about the different responsibilities that will be shouldered by developed and developing nations.

"The problem of climate change cannot be adequately addressed through commitments for emissions cuts by developed countries alone," Perino said.

"Negotiations must clearly differentiate among developing countries in terms of the size of their economies, their level of emissions and level of energy utilization, and sufficiently link the character or extent of responsibility to such factors," Perino said.

The comment seemed aimed squarely at China, a developing nation with an economy that is soon expected to zoom past Germany's to become the world's third biggest, after the United States and Japan.

China also now generates a large share of the world's greenhouse gases, with some experts saying it has already overtaken the United States as the world's No. 1 emitter.

The Bali plan does ask for more from the developing world, giving negotiators the task of considering "mitigation actions" — voluntary actions to slow emissions growth — for poorer countries, including such fast-growing economies as China's and India's.

For industrial nations, the Bali plan instructs negotiators to consider mitigation "commitments," mandatory caps as in the Kyoto deal. But the lack — at U.S. insistence — of ambitious numerical guidelines troubled many environmentalists.

"The people of the world wanted more. They wanted binding targets," said Marcelo Furtado of Greenpeace Brazil.

Climate policy analyst Eliot Diringer, of Washington's Pew center, looked on the positive side.

"It puts no one on the hook right now for emissions reductions," he said. "What's important, though, is that it lets no one off the hook either."