"This clean technology fund is perhaps a Marshall Plan on climate change beginning to emerge where we stop worrying about the short term woes and focus much more on taking a bold step forward ... towards a clean future," de Boer told Reuters.

The Marshall Plan was a major investment project set up by the United States after World War Two to help rebuild Europe's shattered economies.

"The notion of this clean technology fund, announced by the United States, represents a sea change in thinking on climate change," de Boer, the head of the UN Framework Convention on Climate Change, said in a telephone interview from Germany.

"Up to now there has been a lot of concern, certainly in the United States, that helping developing countries like China and India on climate change would take jobs away from Americans and give them to the Chinese," he added.

Few details are yet available about the proposed new fund, such as whether it would be loans or grants, who would administer it and over what period.

Extending the analogy of the Marshall Plan which combined public with private money, de Boer said the clean technology fund would facilitate private investment in clean technologies.

"This clean technology fund is seen as a way of mobilising private capital, of opening up new markets," he said.

"This is a signal that a solution is beginning to emerge, that the conductor that connects rich country action to poor country action in terms of technology and finance is beginning to be seriously thought about," he added.

The fund is expected to draw finance from the major developed nations who have pumped most of the climate warming carbon into the atmosphere in the first place, and who the poorer developing countries insist bear the burden of cost.

De Boer said that while the main thrust of the new fund, announced in Washington on Monday, was to promote low carbon economic growth, security was also a serious issue -- as it was with the Marshall Plan which had a sub text of shoring up European democracies against the threat of Communism.

"I see a number of economic and security issues emerging as a result of climate change which make it all the more imperative to come to grips with this issue in time," he said.