WASHINGTON The United States insisted on Thursday it was serious about global warming and tried to reassure skeptics that President George W. Bush's gathering of major polluting nations would not undermine U.N. efforts.
But some participants and environmentalists were unconvinced, voicing concern that Washington was trying to rally support for voluntary emissions cuts rather than the mandatory reductions called for in the 1997 Kyoto Protocol.
"I want to stress that the United States takes climate change very seriously, for we are both a major economy and a major emitter," U.S. Secretary of State Condoleezza Rice said at the start of the two-day conference.
"Climate change is a global problem and we are contributing to it," Rice said. "Therefore, we are prepared to expand our leadership to address the challenge."
Outside the State Department where the sessions were held, dozens of protesters held up anti-Bush placards, "Bush is a criminal" and "Stop Global Warming Now." Diplomatic security formed a line to stop protesters from entering the building. Nearly 50 demonstrators were arrested.
By most counts, the United States is the world's top emitter of greenhouse gases. But Bush, who rejected the Kyoto Protocol, continues to resist binding targets, calling instead for voluntary approaches and "aspirational" long-term goals.
Rice said individual nations should set their own goals to curb climate-warming emissions, especially carbon dioxide from coal-fired power plants and petroleum-fueled vehicles.
Critics questioned whether such voluntary targets would work.
"We appreciate the sentiments expressed by Secretary Rice, but the devil is always in the detail," South African Environment Minister Marthinus van Schalkwyk told Reuters.
German Environment Minister Sigmar Gabriel said most participants support mandatory targets to cut emissions -- despite U.S. opposition -- and were wary of a process that circumvented the United Nations.
"The good news is that we are negotiating and the United States is willing to negotiate," Gabriel told reporters. "The difficult news is that we are on different sides in questions of substance."
RICH COUNTRIES URGED TO DO MORE
Chief U.N. climate change representative Yvo de Boer told the conference he thought the discussions could contribute to the U.N. process. At a December U.N. meeting in Bali, Indonesia, representatives will consider a way to cut emissions after the Kyoto pact expires in 2012.
De Boer said it was crucial that industrialized countries commit themselves to an aggressive approach that would involve "going well beyond present efforts, given their historic responsibility and their economic capabilities."
U.S. Treasury Secretary Henry Paulson urged countries to eliminate barriers to trade in new environmental technology.
"The future will be built by leaders who recognize that economic growth and responsible environmental stewardship are not incompatible," Paulson said in remarks prepared for delivery at a dinner following the climate change session.
One of the Bush administration's objections to Kyoto was that it exempted fast-growing economies like China and India, while requiring action from rich countries like the United States.
At least one study this year indicated that China is the leading emitter of greenhouse gases, ahead of the United States.
A U.N. meeting on Monday drew more than 80 heads of state and government to focus on the problem of global warming. Bush skipped that meeting although he attended a working dinner hosted by U.N. Secretary-General Ban Ki-moon.
Other participants at the U.S. climate meeting were the European Union, France, Germany, Italy, the United Kingdom, Japan, Canada, India, Brazil, South Korea, Mexico, Russia, Australia, Indonesia and South Africa.
"I do think this meeting is a deliberate attempt to suggest a very different framework for the new international agreement, one that's based on voluntary measures," said Angela Anderson, vice president for climate programs at the Washington-based National Environmental Trust.
But an Indian official said U.S. official had repeatedly said they were not trying to circumvent the United Nations.
"We are fairly reassured on that point now," he said. "The great thing is the U.S. is engaging on climate change."
(Additional reporting by Sue Pleming)