Danish hosts re-launched U.N. climate talks on Thursday after the United States backed a $100 billion (62 billion pound) global fund to support poor countries and world leaders gathered for a final effort to reach a deal.
Ministers urged action as Danish Prime Minister Lars Lokke Rasmussen dropped plans to present his own proposed draft texts which had stalled the process for more than 24 hours -- developing countries had insisted everyone should be involved.
The United States is prepared to work with other countries towards a goal of jointly mobilising $100 billion a year by 2020 to address the climate change needs of developing countries, Secretary of State Hillary Clinton told a news conference.
The European Union has proposed a $150 billion global fund, and the head of the African group of countries Ethiopia's Prime Minister Meles Zenawi on Wednesday supported climate aid for the world's poorest of $100 billion.
Agreement on a climate fund could add political drive to the U.N. talks which meant to agree a host of other measures on Friday, from saving rainforests to boosting carbon markets and stiffening global carbon emissions cuts.
Denmark's Rasmussen removed one obstacle to the talks on Thursday, withdrawing his disputed plan to nominate small groups of countries to storm through complex texts littered with long lists of options.
Negotiators have nearly run out of time to present world leaders with intelligible drafts to sign at the end of the December 7-18 meeting.
The conference is now at a critical juncture and we have now agreed how to proceed, said Rasmussen. We now rely on the willingness of all parties to take that extra step to make that deal that is expected of us.
Earlier on Thursday prospects for a strong U.N. climate pact appeared remote at the climax of two-year talks as ministers and leaders 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.
China is not interested in becoming a party to the efforts by some people to try to blame other countries for 'a failure' at Copenhagen, Yu said.
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.
We are in the end game. It's only a matter of time before the blame game starts, said Ramesh.
Clinton said that any U.S. contribution to a global $100 billion fund for the world's poor depended on developing nations standing behind their actions to curb growth in emissions under a new pact to replace the Kyoto Protocol after 2012.
Clinton said unless developing nations, specifically China, committed to transparency on their emissions curbs, a deal would fail.
Dozens of heads of state arrived in the Danish capital to address the December 7-18 conference.
The summit is meant to agree a global climate deal, as a basis for a legally binding treaty next year, to succeed the Kyoto Protocol after 2012, to avoid dangerous climate change and drive a greener global economy less dependent on fossil fuels.
(With extra reporting by Anna Ringstrom, Alister Doyle, Krittivas Mukherjee, Karin Jensen; Writing by Gerard Wynn; Editing by Dominic Evans)