The atmosphere at the U.N. climate conference grew more tense and divisive after talks were suspended for most of Monday's session _ a sign of the developing nations' deep distrust of the promises by industrial countries to cut greenhouse gas emissions.
With only days left before the conference closes Friday, at least one world leader said he would come early to try to salvage the negotiations, and others reportedly were considering the move.
The wrangle over emission reductions froze a timetable for government ministers to negotiate a host of complex issues. Though procedural in nature, the Africa-led suspension went to the core of suspicions by poor countries that wealthier ones were trying to soften their commitments and evade penalties for missing their targets.
Talks were halted most of the day, resuming only after conference president Connie Hedegaard of Denmark assured developing countries she was not trying to kill the Kyoto Protocol, the 1997 document that requires industrial nations to cut emissions and imposes penalties if they fail to do so. Kyoto makes no demands on developing countries.
Among the issues put on hold: whether China will be asked to make sacrifices similar to those demanded of the United States and other rich nations; whether it will open its carbon books to outside inspection; how to ensure every country counts its carbon emissions the same way; and how to raise a steady flow of money for poor countries to combat climate-linked economic disruptions such as rising seas, drought and floods.
The delay came just days before President Barack Obama, Chinese Prime Minister Wen Jiabao and more than 110 other world leaders were scheduled to arrive to cap two years of negotiations on an agreement to succeed Kyoto.
British Prime Minister Gordon Brown's office said he would go to Copenhagen on Tuesday _ two days earlier than planned _ to try to inject momentum into the talks. Brazil's President Luiz Inacio Lula da Silva and several others reportedly were considering early arrivals.
Former Vice President Al Gore told the conference that new data suggests a 75 percent chance the entire Arctic polar ice cap may disappear in the summertime as soon as five to seven years from now. Gore, who won a Nobel Peace prize for his work on climate change, joined the foreign ministers of Norway and Denmark in presenting two new reports on melting Arctic ice.
The world leaders are aiming for a political agreement in Copenhagen rather than a legally binding treaty. Still, the goal is to nail down individual targets on emissions cuts and financing for developing countries in a deal that can be turned into a legally binding text next year.
Conference officials were struggling to cope with the increasing crush of people, which will only get worse when the leaders arrive with large delegations and their own press corps.
More than 40,000 people applied to attend the conference, already straining to accommodate 15,000. Nongovernment agencies, which sent thousands of people, were told only 1,000 will be allowed in at one time on Thursday and Friday. Journalists will be confined to a media center and forbidden from mingling.
Throngs of newly arrived delegates, journalists and activists waited for hours to pass security and get accreditation Monday, the start of the conference's second and final week. Authorities shut down the subway stop outside the hall because it was too crowded.
Police detained up to 200 people after protesters set fire to street barricades in a downtown Copenhagen neighborhood. Protesters hurled fire bombs at helmeted riot officers who repsonded with tear gas, police spokesman Johnny Lundberg told The Associated Press. He said there were no immediate reports of injuried.
It wasn't immediately clear whether the unrest was connected to the climate conference.
Police briefing detained 1,200 people durimg demonstrations by climate activists over the weekend.
The negotiations were meant to extend the Kyoto pact for at least another five years, with deeper emission targets for rich countries. A separate stream of talks dealt with the United States _ which rejected Kyoto _ and obligations by the developing countries in exchange for tens of billions of dollars a year.
The Africans protested when Hedegaard wanted to lump all the talks together.
"We are seeing the death of the Kyoto Protocol," Djemouai Kamel of Algeria, the head of the 50-nation Africa group, told reporters.
Mohammed Nashid, the president of the Indian Ocean archipelago nation of the Maldives, helped resolve the deadlock with an impassioned speech to the African nations to return to the talks, delegates said.
Outside the conference, Nashid voiced his frustration.
"In all political agreements, you have to be prepared to negotiate. You have to be prepared to compromise, to give and take. That is the nature of politics. But physics isn't politics. On climate change, there are things on which we cannot negotiate," he said.
U.S. special climate envoy Todd Stern said that with leaders due to arrive soon "any lost time is unhelpful." He added that in any complex negotiation "it never goes smoothly, never according to plan. There are always bumps."
Canada's Environment Minister Jim Prentice said the dispute set back the talks. "We have lost some time. There is no doubt about that," Prentice said.
Sakihito Ozawa, Japan's environment minister, said the African demand to spend more time on the industrial nations' targets "wasn't feasible."
"When I listen to the comments made by the developing countries, it made me very worried," he said, accusing those nations of trying to disrupt the conference.
On the sidelines of the talks, U.S. Energy Secretary Steven Chu announced a new program drawing funds from international partners to spend $350 million over five years to give developing nations solar energy systems and other clean energy technologies to poor countries. The U.S. share of the cost will be $85 million, with the rest coming from Australia, Britain, Netherlands, Norway and Switzerland.
The International Energy Agency said $8.3 trillion will be spent on new energy in the next 20 years, but the entire amount could be recovered in cheaper energy and in energy efficiency. IEA director Nobuo Tanaka told reporters 93 percent of the additional energy needed by 2030 will be required by developing countries.
Associated Press writers Michael Casey and Jan M. Olsen contributed to this report.
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