BALI, Indonesia &

Delegates at the U.N. climate conference extended closed-door talks into an extra day Saturday, nearing resolution of a dispute over how far future negotiations should go in trying to cut emissions of greenhouse gases.




U.N. Secretary-General Ban Ki-moon was arriving Saturday morning, either to announce the successful launching of the "Bali Roadmap" negotiations or to help break any lingering impasse.




Yvo de Boer, the U.N. climate chief, said late Friday that talks were going "slower than I had expected," but he expressed optimism the conference was "on the brink of agreement."




"People are working very hard to resolve outstanding issues," he said before talks recessed for several hours overnight.




The negotiating agenda set at Bali, and the results of two years of negotiations to follow, will help determine for decades to come how well the world can hold down its rising temperatures.




Delegates had sparred for days over the wording of the conference's main decision document. The most contentious point was the European Union's push to set a goal of reducing industrial nations' emissions 25 percent to 40 percent below 1990 levels by 2020.




Trying to break the deadlock, the conference president, Indonesian Environment Minister Rachmat Witoelar, proposed revised language dropping explicit mention of numbers while substituting a reference to a U.N. scientific report suggested the 25-40 percent range of cuts.




Witoelar's proposal provided a basis for a long-expected compromise, producing a relatively vague mandate for the two years of negotiations. As worded, his draft "Bali Roadmap" would not guarantee any level of binding commitment by any nation.




On developing countries, including such big emitters as China and India, the draft would instruct negotiators to consider incentives and other means to encourage poorer nations to voluntarily curb growth in their emissions.




De Boer said worldwide public opinion was forcing the more than 180 national delegations to find a way to agree.




"I don't think any politician can afford to walk away from here," he told reporters. Asked if that included the United States, he responded, "Perhaps most of all the United States."




The U.S. has come under intense criticism in Bali, including from former Vice President Al Gore, over the Bush administration's opposition to mandatory emission cuts. But all sides acknowledged that negotiations cannot succeed without the involvement of the United States, the world's leading emitter of greenhouse gases.




The task before the annual U.N. assembly was to launch negotiations on a plan to bring deeper emissions reductions. It is to replace the Kyoto Protocol, which requires 37 industrial nations to cut output of carbon dioxide and other greenhouse gases 5 percent below 1990 levels by 2012.




The United States is the only major industrial nation to reject Kyoto, arguing it would hurt the U.S. economy and also exempted fast-growing economies like China and India.




The Bush administration favors a voluntary approach to bring about emission reductions, rather than internationally negotiated and legally binding commitments.




For years, the rest of the world has sought to bring the Americans into the framework of international mandates. At this point, however, many seem resigned to waiting for a change in White House leadership after next November's U.S. election.




In a series of landmark reports this year, the U.N.'s network of climate 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 warming.




To avoid the worst, the Nobel Prize-winning panel said, emissions should be reduced by 25 percent to 40 percent below 1990 levels by 2020.




The Kyoto Protocol nations have accepted that goal, and the numbers were written into early versions of the Bali conference's draft decision statement &

not as a binding target, but as a suggestion in the document's preamble.




The U.S. delegation opposed inclusion of such numbers. American negotiator Harlan Watson said they would tend to "drive the negotiations in one direction."




Environmentalists accused the U.S. of trying to wreck future talks.




"The United States in particular is behaving like passengers in first class in a jumbo jet, thinking a catastrophe in economy class won't affect them," said Tony Juniper, a spokesman for a coalition of environmentalists the conference. "If we go down, we go down together, and the United States needs to realize that very quickly."




The draft document also called for developing countries to take new steps toward restraining growth in their emissions.




Such actions by China, India, Brazil and others &

not envisioned as legally binding by the draft "Bali Roadmap" &

would be key to winning broad acceptance of deeper, mandatory cuts among richer nations.




The European Union threatened to stay away from separate U.S.-led climate talks next month if Bali didn't endorse 25-40 percent emissions reduction guideline. In those "Major Economies" talks, initiated by President Bush in September, Washington seeks pledges from 16 other nations &

responsible, with the U.S., for 80 percent of global emissions &

to curtail greenhouse gases according to each country's formula.




The Europeans and others showed little enthusiasm for this "voluntary" approach, and environmentalists denounced it as an effort to subvert the U.N. climate treaty process. It remains to be seen whether EU countries will attend the next meeting, in Honolulu in late January.