De Boer said the financial "earthquake" that has seen markets plunge worldwide in recent weeks could damage UN-led climate change talks, but only "if the opportunities that the crisis brings for climate change abatement are ignored."

"The credit crisis can be used to make progress in a new direction, an opportunity for global green economic growth," de Boer, who heads the Bonn-based UN Climate Change Secretariat, told a news conference.

"The credit crunch I believe is an opportunity to rebuild the financial system that would underpin sustainable growth ... Governments now have an opportunity to create and enforce policy which stimulates private competition to fund clean industry."

De Boer said a successful outcome to climate change negotiations in Copenhagen in December 2009 would create new markets, investment opportunities and job creation.

But he warned that "if available global capital is used primarily to refloat the financial world, we literally will sink the futures of the poorest of the poor.

"And I hope that the credit crunch will not mean that people in the South will have to wait for those in the North to have repaid their credit card debts and mortgages before attention is again turned to the South."

Without reaching out a hand to developing countries, it would be very difficult to make advances on the rest of the environmental agenda, De Boer said.

Environment ministers will meet in two months' time in Poznan, Poland, to prepare for the Copenhagen summit, which is due to agree on a new global-warming accord to succeed the Kyoto Protocol, which expires in 2012.

Ministers in Poznan must make clear they were "willing to put financial resources, the architecture, the institutions in place that will allow developing countries to engage in a global approach on both mitigation and adaptation," he said.

Funding did not have to all come from governments and he foresaw "an approach where we very much use the market".

De Boer said the financial crisis had not so far affected the Kyoto Protocol's Clean Development Mechanism, which allows rich countries to offset their carbon footprints by investing in clean energy projects in developing countries.

"I don't see a slowdown in the CDM pipeline at the moment," he said. (Editing by Philip Barbara)