U.S. and European trade officials hoping to open a new front in the global warming battle have failed to win approval for a proposal to eliminate tariffs on environmentally friendly technologies.

The trade officials were meeting on the sidelines of the United Nations climate conference on the Indonesian island of Bali, which involves 190 countries including Canada, and runs until Dec. 14.

Delegates from about 30 countries wrapped up two days of talks Sunday after grappling with how changes to trade policies might help in the fight against global warming.

They talked about a U.S.-European Union proposal to open up trade in solar-powered, wind-powered and related technologies, but India and Brazil both rejected the plan.

Brazilian Foreign Minister Celso Amorim said it falls short because it would not apply to biofuels such as ethanol, which he said has helped Brazil cut climate-warming carbon dioxide emissions.

The South American country has been trying to wean itself from fossil fuel imports for three decades by boosting production of ethanol. Brazil is now the world's top producer of the biofuel.

"I think this list is incomplete," Amorim told reporters. "It won't do much for climate change. It's not proven what the effect it will have on climate change."

Brazil has complained that its sugar cane-based fuel is being held back by high U.S. and European tariffs.

Both India and Brazil described the proposal as "disguised protectionism" to boost exports from rich countries under the pretext of trying to slow climate change.

Delegates to the Bali conference have been trying to lay the groundwork for a new international climate agreement to replace the Kyoto Protocol, which expires in 2012.

A key question is how much wealthy countries should commit to slashing their output of carbon emissions blamed for warming the planet.