Negotiators from almost 200 countries raced to find agreement on the rules that will govern an international treaty on curbing global warming, but the text the Polish diplomat chairing the talks planned to present to delegates Thursday remained under debate as the two-week summit neared an end.

Diplomats and ministers huddled behind closed doors at a U.N. climate summit in Katowice, Poland, weighing every word in drafts that cover issues such as how countries will count their greenhouse gas emissions and tally the effect of efforts to reduce them.

Along with the rulebook for putting the goal of the 2015 Paris climate accord into practice, the main issues at the talks are how much financial support poor countries will get to offset the effects of climate change and whether to send a strong message about future work to curb climate change.

Last week, the United States, Russia, Saudi Arabia and Kuwait blocked endorsement of a scientific report on a key element of the Paris agreement: capping global warming at 1.5 degrees Celsius (2.7. Fahrenheit). The action angered other countries and environmentalists, who accused the four oil-exporting nations of trying to stall progress toward the accord's most ambitious target.

"Tonight is the critical night," Greenpeace Executive Director Jennifer Morgan said. She urged developed countries to keep the rules from getting watered down in the final hours and to ensure poor nations get the help they need.

Mohamed Adow, a climate expert at Christian Aid, said the discussions on financial support seemed to be moving in the right direction, though the overall outcome of the talks was uncertain.

Developing countries have been promised billions of dollars (euros) in aid, loans and other financial support to help them reduce their emissions and adapt to inevitable changes in the world's climate.

Some are also demanding money to make up for the damage already caused by global warming, arguing that rich industrial nations are to blame for most of the emissions of carbon dioxide and other greenhouse gases humans have pumped into the atmosphere.

"Real action requires real money for real solutions," said Adow. "The EU needs to separate itself from the laggards like Australia, Japan and the United States."

While U.S. President Donald Trump has announced he's pulling out of the Paris accord, American officials dangled the possibility that the U.S. might consider rejoining if it gets more favorable terms.

China, which was a key broker of the 2015 accord, dismissed the idea of revising core parts of the pact.

"China and the U.S. have worked together with all other countries to complete the negotiation and thus make the Paris Agreement a milestone achievement in global climate governance," Beijing's chief negotiator. Xie Zhenhua, told reporters.

"We will not reopen negotiations on issues where we have already reached agreement," he said.

Xie also pushed back on demands from rich nations for China to accept the accounting and reporting rules developed countries follow. He noted that while China is the largest single emitter of polluting gases, its gross domestic product per capita remains below the world average.

German negotiator Karsten Sach expressed optimism a deal could be reached, rating the draft texts that emerged between Wednesday night and Thursday morning as "somewhere between seven and eight" out of ten.

"Quite good, but not perfect," he said.

One veteran of global climate talks said it wasn't unusual for negotiations to hit a crisis toward the end, as exhausted negotiators try to reconcile a complex set of drafts with their national interests.

"In a positive way, it's creative chaos," said Hans Joachim Schellnhuber, founder of the Potsdam Institute for Climate Impact Research. "But I do not know how it will be this time."


Associated Press reporter Monika Scislowska contributed to this report.


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