DOHA China led developing nations on Wednesday in demanding rich countries give details of a promised surge in aid to $100 billion a year by 2020 to help the poor cope with global warming.
But most rich nations, facing economic slowdown at home that cut overall development aid in 2011, said they were unable to stake out a timetable for rising aid at deadlocked global climate talks.
"The core issue is finance," Xie Zhenhua, head of China's delegation, told a news conference of a main track of the November 26-December 7 talks among 200 nations in Doha, Qatar, that is a big block to a modest deal to keep U.N. climate efforts on track.
He said a deal on finance would "create very good conditions for the settlement of other issues" in Doha, which is also seeking a symbolic extension of the U.N.'s Kyoto Protocol for curbing greenhouse gas emissions by rich nations beyond 2012.
"Without figures on the table we are not going to have a package," Pa Ousman Jarju of Gambia, who chairs the group of least developed nations, said of calls for new finance.
Rich nations say they have kept a pledge made at a Copenhagen summit in 2009 to provide $10 billion a year in aid to the poor to help them curb their fast-rising emissions and cope with floods, droughts and rising seas from 2010-12.
But the poor want a timetable towards another promise made at the summit, of aid of $100 billion a year from 2020. World leaders did not say what would happen between 2013 and 2019.
"There is every intention of continuing to support climate finance," deputy U.S. climate envoy Jonathan Pershing said.
"These are difficult financial times in Europe," said Pete Betts, a senior British negotiator representing the European Union. "I think that we are not going to be in a position at this meeting to agree any kind of target for 2015."
Separately, U.N. Secretary-General Ban Ki-moon said on Wednesday that he would convene a high-level meeting in 2014 to try to find ways of injecting momentum into sluggish world efforts to tackle climate change.
"Money, Money, Money," a group of WWF conservation activists sang outside the talks, from the ABBA hit of the same name, and one danced in a polar bear suit. They said saving the climate was free compared with trillions of dollars spent on banks.
Some developing nations want a doubling of aid in the years 2013-15, to $20 billion a year.
Germany, Britain and Sweden have promised aid beyond 2012 but most nations have not made clear pledges.
Helen Clark, head of the U.N. Development Programme, also urged a mid-term target for 2015 for rising aid. "There's not going to be a magic cheque written in 2020," she told Reuters.
Overall development aid fell 3 percent last year to $133.5 billion, breaking more than a decade of rises, according to the Organisation for Economic Cooperation and Development.
Also at stake in Doha is the Kyoto pact, which obliges about 35 developed nations to cut their emissions of greenhouse gases by 5.2 percent below 1990 levels in 2008-12.
But Kyoto has been hit by the pullout of Russia, Japan and Canada who say that goals beyond 2012 are meaningless because major emerging nations led by China and India will not have targets. Washington never ratified Kyoto.
"The Doha caravan seems to be lost in a sandstorm," said Ronny Jumeau of the Seychelles, speaking for the Alliance of Small Island States.
(Editing by Pravin Char)