Some Kyoto backers reckon President George W. Bush, via the Asia Pacific Partnership for Clean Development and Climate, is trusting too much in clean technology breakthroughs that might never come or even be sufficient if they do.

"We welcome (technology pacts) as part of efforts to reduce greenhouse gas emissions but they won't do the trick," a European Commission spokeswoman said of the six-nation plan, to be launched in Sydney on Wednesday and Thursday.

"If we are serious about reductions the Kyoto Protocol is the way to go."

Kyoto imposes caps on emissions of greenhouse gases by about 40 nations. The United States, the world's top emitter of such gases, shuns such limits.

Many experts doubt that companies will invest enough in new clean energy technology unless they get a carrot-and-stick approach to help stave off what could be disastrous climate changes ranging from desertification to rising sea levels.

NO DRIVERS

"The new partnership has no real drivers," said David Doniger of the Washington-based Natural Resources Defense Council. "A problem of this size is not going to be solved by a small amount of money and cheerleading."

Doniger, who was a US climate negotiator under President Bill Clinton, urged creation of environmental markets, like in the European Union, to give clean energy producers an advantage over burners of dirty fossil fuels.

"Technologies do not just appear from nowhere; they have to be developed, mostly in response to new markets," echoed Jonathan Kohler, an economist at England's Cambridge University.

"The Americans are right that technology will be the solution...but this plan is not enough."

The new partnership groups nations accounting for 48 percent of greenhouse gas emissions against 35 percent bound by caps under Kyoto.

The EU has set a price on carbon dioxide, the main industrial gas blamed for warming the planet, as a step towards squeezing emissions of heat-trapping CO2 from fossil fuels burnt in thousands of factories and power plants.

European factories and power generators get permits to emit carbon dioxide which will be cut in coming years. Those emitting above quota will have to buy permits in a market where carbon dioxide now trades at about 23 euros ($28) a tonne.

"You need a price for carbon dioxide of about 20-50 euros per tonne and then many of the most advanced technologies become competitive - clean coal, sequestration of carbon dioxide and most renewables," said Ottmar Edenhofer of Germany's Potsdam Institute for Climate Impact Research.

The United States, however, argues that technology has solved many of humanity's challenges, and can do so again without a complicated market system.

NO MIRACLES

Many of its allies are unconvinced.

"Let us not be seduced by the illusion of technology," French President Jacques Chirac wrote in a message to environment ministers at UN talks in Canada last month, warning that there would be no "miracle solutions".

The Kyoto Protocol obliges developed nations to cut their emissions of greenhouse gases by 5.2 percent below 1990 levels by 2008-12. Bush pulled out of Kyoto in 2001, saying it would cost US jobs and wrongly omitted developing nations.

Backers of the US-led plan say it complements Kyoto and is not a rival. Yet comparisons are inevitable. Australian Prime Minister John Howard once said: "the fairness and effectiveness of this proposal will be superior to the Kyoto Protocol."

Doniger said the United States had argued strongly in the 1990s for the creation of markets to rein in climate change.