"I don't think any politician can afford to walk away from here," De Boer told reporters. "Perhaps most of all the United States."
The United States is the only major industrial nation to reject the Kyoto agreement.
The Bush administration instead favors a voluntary approach—each country deciding how it can contribute—in place of 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 officials seemed resigned to waiting for a change in White House leadership after next November's U.S. election, hoping the next administration would agree to tougher targets.
In a series of landmark reports this year, the U.N.'s network of climate scientists warned of severe consequences—including 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 this conference's draft—not as a binding target but as a suggestion in the document's preamble.
The U.S. delegation immediately opposed any inclusion of such numbers, complaining they would tend to "drive the negotiations in one direction," as U.S. negotiator Harlan Watson put it.
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 spokesperson for the environmentalist coalition here. "If we go down, we go down together, and the United States needs to realize that very quickly."
The draft final document also called for developing countries to take new steps toward restraining growth in their emissions. The exemption of such fast-growing economies as China's and India's from the Kyoto pact was a major U.S. complaint.
Such actions by China, Brazil, and others—not envisioned as legally binding by the draft Bali Road Map document—would be key to winning broad acceptance of deeper, mandatory cuts among richer nations.
The EU had threatened to withdraw from separate U.S.-led climate talks if Bali didn't endorse the 25 percent to 40 percent emissions reduction guideline. In those "Major Economies" talks, opened by President Bush in September, Washington is seeking 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.
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