By Alister Doyle
OSLO, Aug 28 (Reuters) - Environmentalists accused U.S. President George W. Bush on Thursday of further undermining international efforts to curb global warming with a likely ruling that carbon dioxide is not a pollutant.
The Natural Resources Defense Council, an environmental group, said on Wednesday, Washington was set to rule both that CO2 is not an air pollutant and that the federal government thus has no authority to regulate emissions.
It said it had been told of the plan by staff from the U.S. Environmental Protection Agency (EPA).
"This is further evidence if any were needed that the Bush administration is merely an extension of the fossil fuel industry," said Steve Sawyer, climate policy director at Greenpeace.
However, the EPA has said the United States' Clean Air Act, under which it defines pollutants, was not designed to address global warming.
The United States, with about four percent of the world population, is the leading polluter and emits about 23 percent of the world's CO2. The average American emits about 19.7 tonnes per year against 0.1 tonne per Rwandan.
The European Union insists it is keeping CO2 -- which occurs naturally as well as being a byproduct of industrial processes -- classified as a pollutant blamed for blanketing the planet, raising temperatures and triggering everything from more frequent heatwaves and droughts to floods and tornadoes.
"It is indeed a pollutant" European Commission spokeswoman Ewa Hedlund said in Brussels, adding that EU legislation states that "it contributes to climate change".
Environmentalists said the U.S. move would be a bad, isolationist example. Many scientists believe human emissions of CO2, from cars and factories, are nudging temperatures up and contributing to raise sea levels or drive species to extinction.
"This is a very bad signal that is being sent to American industry and which is in turn being sent to the rest of the world, saying not only we don't care about it but also that we are going to remove any ability to deal with it," Tony Juniper, a director of Friends of the Earth, said in London.
KYOTO PULLOUT
Bush caused anger abroad in 2001 by pulling out of the Kyoto Protocol, meant to curb global warming mainly by limiting emissions of CO2. Bush argued it was too expensive and wrongly excluded developing nations.
Other nations want to go ahead with Kyoto.
Under a complex voting system, however, Kyoto's fate hangs on ratification by Russia. Moscow said it would ratify but has yet to do so.
"Washington is well aware that Moscow's decision not to ratify the protocol would kill the agreement once and for all, and this is what the United States ultimately wants," said Natalia Oleferenko, a CO2 expert at Greenpeace in Moscow. Russian officials were not available for comment.
Others said the expected CO2 ruling would be no big surprise, given previous Bush's policies. In March 2001, he went back on a campaign promise to impose limits on carbon dioxide from power plants. He had declared in a campaign speech that CO2 was a pollutant.
"In the sense that (U.S.) work on the Kyoto Protocol has been more obstructive than constructive, I doubt it will have too many implications," said Kim Carstensen, head of the WWF environmental group in Denmark.
Greenpeace's Sawyer said countries routinely impose limits on natural substances when they occur in unnatural amounts, such as CO2. Washington imposes limits on ozone, for instance, to reduce smog.
(With additional reporting by Jeremy Lovell in London, Robin Pomeroy in Brussels, Maria Golovnina in Moscow)