The plan is set out in an EU paper outlining the bloc's position ahead of U.N.-led climate talks in Copenhagen in December, meant to agree a new, global climate treaty.

The fund-raising idea is the most specific yet from any rich country or bloc on how to persuade developing nations to agree binding, concrete steps to slow their greenhouse gas emissions -- one of the key obstacles in climate talks so far.

The draft paper to be published next week, and seen by Reuters, calls on rich countries to pay for developing countries to cut their greenhouse gases, called mitigation, and prepare for unavoidable warming, called adaptation.

"All developed countries will need to contribute to financial resources for adaptation and mitigation in developing countries via public funding and the use of carbon crediting mechanisms," it said.

Rich countries should commit to binding limits on their greenhouse gas emissions through 2020. They could then pay a set price for every ton of emissions, the paper said, under one of "two principal options to generate funding."

The other option would be to pay at rates per ton on a global carbon market, and so not guarantee a price.

If widely agreed the plan could encourage the world's top carbon emitter, China, to agree to internationally binding climate measures. That in turn could satisfy a general pre-condition made by the second biggest emitter, the United States, for signing up to a successor to the Kyoto Protocol.

The United States did not ratify Kyoto because the pact contained no concrete commitments by developing countries, a position the new Obama administration is likely to maintain regarding a successor pact after 2012.

The EU paper said that if the main developed countries paid 1 euro per ton of greenhouse gases in 2013 rising to 3 euros in 2020, that would raise 164 billion euros ($213 billion) over the period.

It called for a gradual phasing out of carbon offsetting, which allows rich nations to lay off their greenhouse gas emissions by paying for cuts in developing countries.

The EU is the world's biggest buyer of carbon offsets, and last month agreed climate targets which allowed EU states and companies to offset up to 3 billion tons of their greenhouse gas emissions from 2008-2020, or more than the annual emissions of the Netherlands.

Carbon offsetting allows developing countries, which at present face no binding climate targets, to earn money in return for curbing greenhouse gases.

The EU wants to phase out that option for "advanced developing countries," which the paper said should face binding caps instead. But it gave no timeline for the change.