BANGKOK, Thailand - China accused rich countries Monday of slowing progress at the UN climate talks, contending they are spending their energy trying to dismantle the Kyoto Protocol rather than negotiating the hard targets necessary to reduce emissions.

Yu Qingtai, the country's top climate envoy, did not single out any country for criticism but complained that industrialized countries as a whole were trying to change the rules of the game just weeks before world leaders meet in Copenhagen to forge a new climate pact.

"In my view, the fundamental reason for a lack of progress is the lack of political will on the part of Annex 1 countries," Yu said, using a term that refers to industrialized countries.

"Are we prepared to take real action to match our words? Are we serious about our commitments?" he continued. "This is the question we all need to ask ourselves two months before Copenhagen."

Yu's comments come at the halfway point of talks in Bangkok on a climate treaty that would replace the Kyoto Protocol, which expires in 2012. Negotiators are tasked with trying to reduce an unwieldy, 200-page document down to something more manageable before Copenhagen.

While key issues like emission targets and financing are unlikely to be solved here, Yu's comments indicate a growing rift between rich and poor nations in the climate talks and foreshadow some of the difficulties that are expected to emerge in the coming weeks.

For months, negotiations have been deadlocked. UN climate chief Yvo de Boer told The Associated Press last week that there was growing frustration among developing countries that they are offering to take action to reduce their own emissions but were not seeing comparable commitments from rich countries.

Now, the poor countries are seizing on a less visible aspect of the debate -- the legal framework of a new Copenhagen pact.

Most poor countries want to keep the framework of the Kyoto pact, which commits 37 wealthy nations to cut greenhouse gas emissions an average of 5 per cent below 1990 levels by 2012 but doesn't require any binding commitments of developing countries.

President George W. Bush rejected the 1997 Kyoto global warming pact, contending that it was unfair not to require developing countries to curb emissions. The United States is the only major industrialized country that did not ratify the pact.

Australia, the United States and Japan have offered up a range of proposals in Bangkok on a new framework that critics complain would aim to weaken Kyoto by not requiring emissions cuts to be internationally binding. It would be up to individual governments to enforce whatever cuts they had agreed to.

Poor countries also complain the proposals aim to require similar actions of developed and developing nations, something they oppose since industrialized countries are responsible for a bulk of greenhouse gas emissions.

Yu complained the proposals would lead to the termination of the Kyoto Protocol and everything it represents was not a "fair way of negotiating" -- though he stopped short of saying it would prevent a deal in Copenhagen.