The U.S. and China exchanged barbs Wednesday at the Copenhagen climate talks, underscoring the abiding suspicion between the world's two largest carbon polluters about the sincerity of their pledges to control emissions.
U.S. chief negotiator Todd Stern urged China to "stand behind" its promise to slow the growth of the country's carbon output and make the declaration part of an international climate change agreement.
China rejected that demand, and renewed its criticism of the U.S. for failing to meet its 17-year-old commitment to provide financial aid to developing countries and to reduce emissions of carbon dioxide and other gases warming the Earth.
"What they should do is some deep soul-searching," said Yu Qingtai, China's chief climate negotiator.
The remarks during separate news conferences reflected the heavy lifting that remains in the 10 days before 110 heads of state and government conclude the summit, which aims to create a political framework for a treaty next year to succeed the 1997 Kyoto Protocol.
President Barack Obama helped break the ice in the troubled negotiations last month, saying he would deliver a pledge at Copenhagen to reduce U.S. greenhouse gas emissions by around 17 percent from 2005 levels by 2020. It will be the first time the U.S. has committed to a reduction target.
China responded a day later, announcing it would voluntarily reduce the carbon intensity of its industry by up to 45 percent, meaning its emissions would continue to grow but at a rate lower than the economy.
Stern said China's announcement boosted optimism before the conference, but didn't go far enough.
"What's important is not just that they announce them domestically but they put them as part of an international agreement," Stern said.
Whatever actions the Chinese take to slow emissions growth should be transparent, he said, "it's not just a matter of trust."
The Chinese delegate accused the Americans and other wealthy countries of insincerity when they signed the 1992 climate convention promising voluntary carbon reductions. The convention was amended five years later in Kyoto, making reductions mandatory for most industrial countries. The United States rejected the protocol because it did not include China or India.
During the talks Wednesday, the tiny Pacific island of Tuvalu seized the initiative with a demand that the conference go beyond a political deal and negotiate a new protocol with the same legal standing as Kyoto.
Tuvalu and other island nations are threatened by rising sea levels that scientists say will engulf low-lying areas as Arctic ice sheets and mountain glaciers melt.
"Our future rests on the outcome of this meeting," said Tuvalu delegate Ian Fry.
But in an unusually open split among the developing countries, China refused to support Tuvalu's motion for an open debate on its draft protocol. The procedural rebuff doomed the island state's initiative.
Outside the conference hall, about 100 activists hastily arranged a noisy demonstration in support of Tuvalu, prompting U.N. police to close off the plenary area and to eject anyone in the hall without the correct badge.
Environmental campaigners have threatened disruptions over the weekend, raising fears of violence and rioting.
Danish police raided a building that the city of Copenhagen had loaned to political activists and found shields and fluorescent tubes filled with a mixture of oil and paint, apparently meant to be used in Saturday's protest, said police spokesman Rasmus Bernt Skovsgaard. No arrests were made.
U.S. Environmental Protection Agency chief Lisa Jackson, meanwhile, said her agency's decision that greenhouse gases should be regulated would be a dual path of action by the Obama administration and Congress.
The EPA determined Monday that scientific evidence clearly shows they are endangering the health of Americans, and that the pollutants _ mainly carbon dioxide from burning fossil fuels _ should be regulated under the Clean Air Act. That means the EPA could regulate those gases without congressional approval.
The EPA decision was welcomed by nations that have called on the U.S. to boost its efforts to cut greenhouse gas emissions. Those nations believe Obama could act more quickly and bypass legislation slowly working through Congress.
The full Senate has yet to take up legislation that cleared its environment committee and calls for greenhouse gases to be cut by 20 percent by 2020, a target that was scaled back to 17 percent in the House after opposition from coal-state Democrats.
"We have been fighting to make up for lost time," Jackson said, referring to the Bush administration's rejection of Kyoto.
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