But industry lobbyists in the US have resisted moves to certify timber. A US state department memo leaked to the BBC's Newsnight shows that the US will refuse to sign up to the Benn initiative.

The state department head of forest policy, Stephanie Caswell, drafted a strategy in January designed to scupper the Benn plan, an "Input to strategy paper for G8 environment and development ministerial". Under what she described as "watch out items" is timber procurement. She said that "new import regulations/restrictions are unacceptable. We do not support issuance of 'action plan' by ministers. It should not be highlighted." The paper adds that the "US will work with Canada to hold back procurement actions and with Russia and Japan to dissuade them from supporting UK".

A state department spokesman confirmed that the paper was genuine, but said it was never formally accepted as US strategy. He confirmed that the US had reservations over proposals for new rules on timber procurement in America, but insisted that in this week's negotiations the US would allow other G8 partners to decide whether to support Mr Benn's scheme.

He said the US "might have had some discussions with Japan on the fringes of meetings about the issue" in G8 preparatory meetings, but said the Japanese would make up their own minds.

Europe is strongly backing Mr Benn's initiative, and the US tactics drew a furious response from rainforest campaigners. Faith Doherty of the Environmental Investigation Agency in the UK said: "This is outrageous. US business simply doesn't want any restrictions on its own practices."

Japan's foreign ministry told Newsnight that its position was much closer to the UK than to the US. It is understood that Russia is also lining up with the Europeans.

Agus Setyarso, an Indonesian expert on forests who works with Mr Benn's department, said the Indonesian government could not contain the organised crime rings carrying out the illegal logging without help. "The problem cannot be attacked from within the country, but from the market side. What we are asking from developed countries is twofold. One is to stop buying illegal timber from producer countries. The second is to help us in bringing back the systems in our country in such a way that the market and the law enforcement can be back to normal."

A department spokesman said it did not comment on leaked memos, and that negotiations over the statement for the end of the G8 meeting were continuing. Privately, however, officials were said to be angry at the US's refusal to join international efforts.

Other observers feel the state department's position is driven by free-market ideology. Forest campaigners say the US position is a serious blow, because if all the G8 nations signed up to the Benn plan it would guarantee that a substantial proportion of world timber was properly produced and send a clear signal to companies and exporting nations about the direction of future policy.

In an echo of the debate over climate change, the US is sceptical about G8 timber policies because China is a huge importer of stolen timber. Campaigners say China is unlikely to change unless rich countries put their house in order.