Wealthy countries would pay poor nations not to cut down their trees under a proposal that is gaining support at an international conference on climate change in Montreal.

The idea comes from Papua New Guinea, a South Pacific nation where hundreds of people living on an offshore atoll face imminent evacuation because of rising water levels attributed to global warming.

Supporters say protecting a rain forest is as important to reversing global warming as cleaning up gas-spewing factories and developing clean energy alternatives.

Papua New Guinea's proposal, introduced on Wednesday, is aimed at developing nations not bound by greenhouse gas emissions reductions mandated under the Kyoto Protocol.

Only the top 35 industrialized nations that signed the 140-nation accord are required to cut emissions to 5.2 percent below their 1990 levels by 2012 in an effort to curb global warming.

The proposed scheme would financially reward developing countries for preserving rain forests, which produce oxygen that helps clean the air. Some scientists maintain that deforestation contributes to about 20 percent of greenhouse gases.

"We have joined with many like-minded developing countries that may be prepared to begin, on a voluntary basis, reducing our carbon emissions from deforestation subject to the creation of meaningful incentives," Papua New Guinea's Environment Minister, William Duma, told the U.N. Climate Change conference in Montreal.

The proposal generated a buzz and was backed by powerful countries including Australia, Japan and EU members before the conference opened on Montreal.

In the week before the conference, Papua New Guinea was preparing to evacuate hundreds of people living in the low-lying Carteret atoll, which is sinking because of rising water levels in the Pacific.

Robert Aisi, Papua New Guinea's ambassador to the United Nations, told The Associated Press on Thursday that he had been getting "generally positive" feedback, but consultations had just begun.

"Let's be very frank; this is just a start," he said. "Part of the proposal is to work out where the money would come from. I would hope that we can come up with a mechanism."

One of the mechanisms under Kyoto, which went into effect in February, allows a system of bartering carbon emissions.

If Germany, for example, is reluctant to clean up a particularly lucrative, but dirty power plant, it can still earn credit toward its mandatory emissions cuts by investing in sustainable technology in another country — or, say, buying up a slice of forest in Papua New Guinea and not tearing down the trees.

The United States, which produces one-fourth of the world's pollution, has refused to join Kyoto. President Bush said it would harm the U.S. economy and his delegates at the conference insist the White House will not be a part of any mandatory emissions cuts.

U.N. Ambassador Aisi said Washington has not backed his proposal but "they have not said no."

When Bush pulled out of Kyoto, his administration said it would help fight climate change by saving tropical forests, said John Niles of the Washington-based Climate Community and Biodiversity Alliance. He said Kyoto signatories are now realizing that the decision to exclude reforestation from Kyoto funding was a mistake.

"Papua New Guinea made the convention realize that it forgot to deal with 20 percent of the emissions," Niles said.

Papua New Guinea has the world's third-largest tropical forest and as an island-nation is particularly vulnerable to climate change.

Duma, the country's environment minister, said emissions cuts by industrialized countries alone cannot prevent global warming.

He said tropical deforestation is "the single largest sector for carbon emissions within the developing world — up to 20 percent of global carbon emissions during the 1990s."

While developing countries are not legally bound by Kyoto — including the big polluters China and India — they are still launching initiatives to fight climate change, said Rafael Senga of the World Wildlife Fund in the Philippines.

"They can feel it, and are actually experiencing the impact of climate change," he said.

While Papua New Guinea can count on the support of a number of countries, the proposal is still being debated within developed countries Senga says.