They may seem to the president like a big step forward but I'm afraid that for the rest of mankind they're actually a big step backward

Democratic Party Senator Joe Lieberman

Japan's Environment Minister Hiroshi Oki said he appreciated Mr Bush's efforts but Tokyo was still not satisfied that they went far enough. Japan hosted talks that led to the Kyoto accord.

However, Foreign Minister Yoriko Kawaguchi welcomed Mr Bush's proposals, saying they showed his serious intention of addressing the issue of climate change.

She added Tokyo would continue to lobby Washington to accept the Kyoto accord.

Biggest polluters

However, the German Government said the US plan was unlikely to lead to cuts in emissions.

	1. Burning of fossil fuels increases atmospheric levels of carbon dioxide and other greenhouse gases 2. These trap some of the sun's energy and reflect the heat back down to earth. 3. Some scientists argue increased levels of greenhouse gases leads to overheating, causing global warming Click here for animated graphic showing the Greenhouse Effect

"Because of its non-binding character, one can hardly expect the programme to significantly lower the already high US emissions, if at all," Environment Minister Juergen Trittin said.

And his French counterpart, Yves Cochet, has called on the European Union to oppose Mr Bush's plans and urge him to ratify the Kyoto protocol instead.

For its part, China called on Washington to take the lead in cutting greenhouse gases.

"Developed countries have the duty to take the lead in taking action to reduce greenhouse gas emission, because historically and at present, they are the main emitters of greenhouse gas," a Chinese foreign ministry statement said.

Announcing the plan on Thursday, Mr Bush argued that economic growth is the key to environmental protection because it pays for the means to invest in cleaner industries.

Unfair exemptions

Mr Bush said the Kyoto treaty would have put millions of people out of work because of its mandatory reductions.

Bush's proposals

Cut ratio of emissions to US GDP growth by 18% over 10 years Tax incentives to reduce sulphur dioxide, nitrogen oxides and mercury emissions Increase 2003 budget by $700m to $4.5bn to fund initiatives

It was unfair, he said, because it would have penalised the US and exempted many developing countries such as India and China.

The main difference between the Bush initiative and the Kyoto treaty is that it proposes goals rather than mandatory reductions and a relative rather than net reduction in emissions.

Reaction was also mixed in the United States itself.

The Democrat leader in the House of Representatives, Dick Gephardt, said Mr Bush was more interested in helping energy companies than achieving genuine cuts.

But Peter Raven, president of the American Association for the Advancement of Science welcomed the proposal.

"President Bush came in highly sceptical about the basis for global warming but has become convinced that it is a real problem for the world," he said.

"The speech... is a very reasonable beginning."