Swedish businessman and ex-Tory donor Johan Eliasch was commissioned by Gordon Brown to look at ways to protect "lungs of the world". Rainforest destruction accounts for about a fifth of the carbon emissions, blamed for fuelling climate change.

The report is expected to say the best way forward is to make it financially worthwhile for countries with rainforests to protect endangered areas. Campaigners fear the money could end up in the wrong hands and indigenous people could be driven out of rainforests.

The most likely way forward would be to create "forest off-set credits" that will be traded between countries as part of the existing carbon markets that already trade a limited amount of carbon emissions between industries. Andy Tait, head of biodiversity at Greenpeace, said this would destabilise the market and encourage developed countries to buy off-sets rather than cutting carbon or investing in renewables.

He said: "It's clear that protecting the world's tropical forests is vital if we are to beat climate change, but our fear is that these recommendations will propose including forest credits in existing carbon trading schemes. This could lead to major polluters just trying to buy their way out of emissions reductions at home, using forest credits as a cheaper option than investing in domestic clean energy projects and energy efficiency schemes. We need to see both a revolutionary approach to energy and efficiency in Britain, as well as a concerted effort to protect forests abroad. For the sake of the climate, it's not either or, we have to do both."

Instead Greenpeace is recommending that forest credits make up an independent market so protecting rainforests does not take away from cutting carbon. The findings of the report will inform the forthcoming UN Climate Change conference in Copenhagen in 2009 when the world will agree a new way forward to replace the Kyoto Protocol.

The Prince of Wales's Rainforest Project has suggested an "eco-systems" market worth billions of pounds where investors pay to ensure rainforests are protected. Mr Eliasch, who lent £2.6m to the Conservatives and was one of four major donors questioned by police investigating "cash for peerages" claims, had to resign from his post as Tory deputy treasurer to advise the prime minister on forests.

A former chairman of the Young Conservatives, his wealth comes from Head, the Dutch sports equipment company, which he runs from London.  He founded the charity Cool Earth which encourages people to donate money to buy tiny sections of the rainforest to save them from destruction.

(By Louise Gray, Telegraph, 13/10/2008)