(AP) -- U.N. climate talks being held in China this week are making limited progress as rich and poor nations remain divided on key issues, negotiators said Wednesday.
"There is less agreement than one might have hoped to find at this stage, and it's going to require a lot of work to get to some significant outcome by the end of this week," said chief U.S. negotiator Jonathan Pershing.
Delegates from more than 150 nations are meeting in the northern city of Tianjin in the weeklong negotiations ahead of major climate talks in Mexico in December aimed at achieving a global plan for curbing "greenhouse" gases blamed for global warming.
Last year's U.N. climate summit in Copenhagen disappointed many environmentalists and political leaders by failing to produce a legally binding treaty on limiting such gases, such as carbon dioxide. Instead, nations agreed to a nonbinding political declaration on fighting climate change in which countries submitted voluntary pledges to reduce carbon emissions.
Since a binding global deal is largely out of reach for this year, negotiators have been focusing on smaller initiatives that can lay the foundation for a legal framework that could be approved later, possibly at talks in South Africa in 2011.
But even with lower expectations, sharp disagreements remain over how to cut greenhouse gases.
Top Chinese climate official Xie Zhenhua said developed nations have failed to take the lead in making substantial cuts in their own carbon emissions while unfairly demanding more from developing nations.
"The commitments made so far are far from what we expected," he said.
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