COPENHAGEN (Reuters) -- Environment ministers were facing grueling negotiations to salvage a climate pact from half-finished draft texts after two years of talks ran out of time.
Dozens of heads of state are descending on Copenhagen to address the two-week conference, hoping to sign on December 18 a new pact to tackle global warming.
They will find draft texts littered with incomplete choices, exposing long-running rifts between rich and poor countries on how to split the cost of fighting climate change.
Some ministers warned that slow, often stalled talks during the summit meant it was staring at failure.
"We may not get there on the substance, it is quite possible we'll fail on the substance, but at least let's give it a try," said Britain's energy and climate minister Ed Miliband. "At the moment the problem is we're not giving it a try."
Denmark said it was trying to simplify several complex draft negotiating texts to help about 120 leaders attending a high-level summit on December 17 and 18 to agree on a deal.
Access to the conference center, which until now has been bustling with activists, lobbyists, and journalists, will be tightened to protect more than 120 heads of government.
Speakers are lined up to address the summit until the small hours of the morning, and the day is packed with political heavyweights including Iranian President Mahmud Ahmadinejad, Germany's Chancellor Angela Merkel, Brazilian President Luiz Inacio Lula de Silva, and French President Nicolas Sarkozy.
Developing nations rejected Denmark's effort to select small negotiating groups to storm through the labored draft texts, saying the process had to be fully inclusive.
Developed and developing nations are at odds over who should cut emissions, how deep the cuts should be, and how much funding should be provided to poor countries to help them shift to greener growth and adapt to a warmer world.
While the overall picture is bleak, there has been some progress in areas critical to reaching a deal.
Africa dramatically scaled back its expectations for climate aid from rich nations, and Japan pledged about $11 billion in public funds to 2012 to help poor countries adapt to a warmer world and cut their emissions.
Talks on a UN-backed system to pay poorer nations to curb deforestation have advanced, and the United States pledged $1 billion in short-term funds to conserve tropical forests.
A major sticking point between the world's top emitters, the United States and China, has been the question of how they will prove they are sticking to emission-curbing plans.