Whether developed countries fulfill their obligation to provide financial support to poor nations will be a benchmark for the UN Climate Change Conference, Chinese Premier Wen Jiabao said Thursday.

"It is a legal obligation assumed by developed countries to provide developing countries with adequate, additional and substantive financial support."

"Whether we can do it or not will be an important benchmark for the success or failure of Copenhagen," Wen was quoted as saying by Chinese Vice Foreign Minister He Yafei at a press conference.

Wen, who arrived here Wednesday evening for the UN Climate Change Conference, urged developed countries to listen carefully to developing countries, especially the least developed countries (LDCs), island countries and African countries.

"So we can move the negotiation to a good end," Wen was quoted as saying.

Negotiators from more than 190 countries are running against time on Thursday to wrap up the 11-day talks here, hoping to seal a deal to move forward the global fight against climate change before world leaders meet on Friday.

The United States said on Thursday that it was prepared to join other rich countries in raising 100 billion U.S. dollars annually by 2020 to help developing countries combat climate change, but it set a condition that emerging countries should accept international monitoring of its mitigation action.

Rich countries also signaled their intention to commit 10 billion dollars a year to help poor nations in the three years up to 2012, when the first commitment period of the Kyoto Protocol ends.

The Chinese premier said that China has urged developed countries to fully appreciate the concerns and difficulties that developing countries face, especially LDCs, island countries and African countries.

Despite the fact that China is a developing country which still has 150 million people living below the poverty line, China has provided assistance to the least developed countries, island countries and African countries to the best of its ability within the framework of South-South cooperation.