The United States and China took steps Thursday toward a broad agreement that could be sealed by President Barack Obama and Premier Wen Jiabao when they arrive at the flagging U.N. climate talks.
Many leaders mentioned risks of failure at a two-day summit that started with a gala dinner for about 120 world leaders at Christiansborg Palace, hosted by Denmark's Queen Margrethe.
U.S. backed a $100 billion climate fund to help poor nations, Reuters said.
That's a "good first step," China's vice foreign minister, He Yafei, said later.
Earlier on Thursday, prospects for a strong U.N. climate pact seemed remote as nations blamed leading emitters China and the United States for deadlock on carbon cuts. But ministers and leaders urged fresh urgency.
"Copenhagen is too important to fail," China's climate change ambassador Yu Qingtai said, adding that the presence of Premier Wen Jiabao, who arrived in Copenhagen on Wednesday evening, was testament to China's commitment.
The diplomatic duel between Washington and Beijing has marked the two weeks of climate talks, which ground to a near-halt Wednesday as a chronic rich-poor divide flared into the open again, dimming the hopes of the Danish hosts for a comprehensive deal — a preliminary framework for a formal treaty next year on combating climate change.
European Union Commission President Jose Manuel Barroso said the offer of U.S. gave the talks "political momentum."
Failure in Copenhagen "will be catastrophe"
"Time is against us, let's stop posturing," French President Nicolas Sarkozy said in a speech to leaders. "A failure in Copenhagen would be a catastrophe for each and every one of us."
Environment ministers planned to work late into the night on draft texts outlining curbs on greenhouse gas emissions as part of a 193-nation deal due on Friday to avert more floods, heatwaves, droughts and rising sea levels.
The United States, the number two emitter of greenhouse gases behind China, helped the mood by promising to back a $100 billion a year fund for poor nations from 2020. President Barack Obama will arrive early on Friday.
"The United States is prepared to work with other countries toward a goal of jointly mobilizing $100 billion a year by 2020 to address the climate change needs of developing countries," Secretary of State Hillary Clinton told a news conference.
Such funds would be more than all current aid flows to poor nations, a U.N. official said, and in line with demands put forward for African nations. "That's very encouraging," U.N. Secretary-General Ban Ki-moon said of the U.S. pledge.
Less deal possibility
A U.S. official said Obama was unlikely to be more specific about U.S. commitments to help provide funds for poor countries.
A few Greenpeace activists carrying signs saying "Politicians talk, leaders Act" walked straight up the red carpet into Christiansborg Palace after arriving in a motorcade in front of Clinton, Greenpeace said. They were removed by guards.
Accord on finance is one part of a puzzle that also includes a host of other measures, such as saving rainforests, boosting carbon markets and stiffening global carbon emissions curbs.
"If each and everyone does a little bit more than we can do this," German Chancellor Angela Merkel said. She said the European Union was willing to do more but would not act alone.
But any deal will have to be agreed by unanimity. Some small island states and African nations -- most vulnerable to climate change -- insist they will not agree a weak deal.
"We are talking about the survival of our nation," said Prime Minister Apisai Ielemia of the Pacific island state of Tuvalu of the talks that began two years ago in Bali, Indonesia.
The talks, deadlocked for 24 hours, resumed after Danish Prime Minister Lars Lokke Rasmussen dropped plans to present his own compromise texts. His plan had been opposed by poor nations which insisted everyone should be involved.
The draft texts include possible goals such as halving world greenhouse gas emissions by 2050 or obliging developed nations to cut their emissions by between 25 and 40 percent by 2020.
"We are moving out of the valley of death. We are beginning to see the outlines of a compromise, helped by the U.S. offer on finance," said Kim Carstensen, head of the WWF environmental group's global climate initiative.
India's environment minister Jairam Ramesh accused rich countries of planning a "propaganda campaign" to blame developing nations for any breakdown. Developing economies are expected to add almost all future growth in carbon emissions.
Clinton said a deal would fail unless developing nations, specifically China, committed to transparency on their emissions curbs.
The $100 billion, a number first suggested by British Prime Minister Gordon Brown, falls short of what experts say would be needed. The World Bank and others estimate the long-term climate costs for poorer nations, from 2020 or so, would likely total hundreds of billions of dollars a year. China and other developing countries say the target should be in the range of $350 billion.
More immediately, the conference has been discussing a short-term climate fund to help developing countries — a $10 billion-a-year, three-year program. European Union leaders last week committed to supplying $3.6 billion a year through 2012. On Wednesday, Japan, seeking to "contribute to the success" of Copenhagen, announced it would kick in $5 billion a year for three years.
Under the 1997 Kyoto Protocol, 37 industrialized nations that must cut their emissions — not including the U.S., which rejects Kyoto — are required to file detailed reports to the U.N., where they are subject to review.
Experts' estimates of carbon dioxide emissions are based on fuel going into power plants and complex formulas based on power plant efficiency. But those estimates are also dependent on reliable information about fuel and efficiency; they could be skewed by inaccurate input.
The detailed talks on a range of issues — from emissions commitments, to preventing deforestation, to transferring clean-energy technology — reached an impasse Wednesday when developing nations objected to the process that produced a core draft document.
In China, so many new coal-fired plants are being built that it is difficult for international energy experts to figure out the precise carbon dioxide output.
The U.S. came under renewed pressure to improve its pledge of greenhouse-gas emission cutbacks — by about 17 percent by 2020, compared with 2005 figures. That's only a 3 percent to 4 percent reduction from 1990, the benchmark year for the Kyoto countries and the basis for the EU's pledge to cut emissions by at least 20 percent by 2020.