Speaking after talks in Washington with EU officials on November 3, he said they agreed they should create a framework for progress.

The Copenhagen talks are aimed at negotiating a follow-on agreement to the Kyoto Protocol.

Meanwhile, former US Vice President Al Gore says he believes President Obama will attend the talks in Copenhagen.

He said the president would want to emphasise his administration's commitment to safeguarding the environment.

But Mr Obama's allies in Congress are struggling to push through legislation to reduce greenhouse gas emissions, and it is unlikely that any bill will be passed before the December talks.

UN Secretary-General Ban Ki-moon has said world leaders are unlikely to agree on a comprehensive treaty in Copenhagen. He said it was more likely there would only be agreement on principles.

UN officials have also recently declared there is no chance of agreeing all elements of a new legally-binding UN treaty before the end of the year.