EU leaders pledged to pay their "fair share" into an annual global fund for developing nations _ but didn't say how much they would actually contribute. They say some ⁈llion ($148 billion) is needed and that up to half of that should come from governments around the world.

Environmentalists blasted the 27-nation bloc for failing to seize a crucial high ground that could press the world's two largest polluters, the U.S. and China, toward cutting greenhouse gas emissions when a new climate change treaty is negotiated in Copenhagen less than six weeks away.

The money aims to encourage poor countries into using less energy, relying more on renewable power and protecting forests that can absorb significant amounts of carbon dioxide.

EU leaders said in a statement that all countries now need "to inject new momentum" into stalled talks on a pact to keep global temperature increases under 2 degrees Celsius (3.6 degrees Fahrenheit).

"The pace of the negotiations must be stepped up," they said.

The Copenhagen summit is seen as a watershed moment for fighting climate change and for global cooperation, and for years the EU has challenged other powers _ above all, the United States _ to match Europe's commitment.

With U.S. negotiators hamstrung by Congress, which has yet to approve U.S. emissions targets, poorer countries were hoping the EU would set the standard for other industrialized countries to match.

Europe's strong rhetoric on the world stage is often hamstrung by the difficulty of striking any deal _ especially on money _ among 27 members.

The EU executive suggested in September that EU governments could give up to ⁈lion ($22 billion) a year from 2013 to 2020. EU leaders didn't endorse that Friday, saying they would continue to discuss how much to give.

German Chancellor Angela Merkel said Europe should contribute about a third to the global climate fund. She didn't give a figure.

On Friday, vocal advocates for climate funding, such as Britain and Sweden, had to bow to nine poorer eastern EU states who balked at handing out aid when their own budgets were stretched to the limit by the global financial crisis.

EU leaders said they would not require EU states to contribute to the fund before 2013. EU climate donations to developing nations from 2010 to 2012 would be voluntary, they said, weakening earlier promises.

Oxfam and Friends of the Earth said Europe's pledge was not nearly enough, claiming the EU and the U.S. should donate at least ⁈lion ($52 billion) a year each.

Swedish Prime Minister Fredrik Reinfeldt, who led the talks between EU leaders, insisted that the funding promise put Europe ahead of the United States and others in seeking a strong Copenhagen deal.

A panel of U.N. scientists has recommended that developed countries make cuts of between 25 percent and 40 percent of greenhouse gas emissions by 2020 to avoid a catastrophic rise in sea levels, harsher storms and droughts and climate disruptions.

The EU is aiming for far deeper cuts in emissions than most other industrialized nations _ pledging to move from a 20 percent cut below 1990 levels to 30 percent if other regions make similar moves. By 2050, it wants to eliminate most emissions, with a target of up to 95 percent.

The U.S. is considering a far lower cut _ 17 percent from 2005 levels or about 3.5 percent from 1990. Japan has promised a 25 percent reduction from 1990 levels. Per head, Americans account for twice the emissions compared to Europeans and Japanese.

Danish Prime Minister Lars Loekke Rasmussen, who will host the U.N. talks in Copenhagen, downplayed the EU's failure to agree a funding figure, saying "this is not about money."

"This is about reducing the manmade temperature rise," he said. "We want to avoid poverty, farmland erosion and climate migration."

___

Associated Press writers Constant Brand, Raf Casert, Robert Wielaard and Barbara Schaeder in Brussels and Jan Olsen in Copenhagen contributed to this report.