By Elizabeth Blunt BBC, Milan

The US says it is pouring money into new technologies

It wants greenhouse gas emissions to be cut not by what it calls "command and control" but by voluntary action and development of new energy technology.

The US decision not to cut emissions via the Kyoto Protocol is the main reason for the treaty's stagnation.

But the US has now come back centre-stage after two years of lying low.

President George W Bush pulled out of the Kyoto agreement in 2001.

Parallel tracks

The American delegation has already hosted the very first press conference of the Milan meeting and unveiled a multi-media exhibit about US achievements.

Their message is that the US has nothing to be ashamed of, that it has domestic policies in place to combat climate change and is pouring money into scientific research and the development of new technologies.

The chief American negotiator, Harlan Watson, told journalists that the US could match its record with anybody in the world.

The problem for most other delegations is that all this admirable activity is running along parallel tracks, totally separate from the policies being pursued by everybody else.

The rest of the world is trying to put an absolute cap on carbon dioxide emissions.

The US is trying to reduce what it calls the carbon intensity of its economy.

It may get more productivity for the amount of fossil fuels it uses but its greenhouse gas emissions, already the highest in the world, will still continue to rise.