Climate deal 'unlikely' - UN chief

The UN's top climate official has admitted that a final global warming treaty will be impossible this year.

But Yves de Boer, the secretary-general of the UN climate change secretariat, said the principles of a settlement must be settled at the Copenhagen conference in December.

"Time is running out - we do not have another year to sit on our hands," he said.

De Boer added he thought the key to reaching an accord during the conference would be for wealthy countries to offer a financial package to help the developing world adapt to inevitable climate changes and to shift toward low-carbon technologies.

"It is physically impossible to finalise all the details of a treaty in Copenhagen," Mr de Boer said.

"But the meeting must agree on the political essentials that make a long-term response to climate change clear, possible, realistic and well-defined."

He called on the European Union, whose leaders begin a two-day summit tomorrow in Brussels, to declare the EU's financial contribution, which he said would push developing countries to announce their own programme for limiting the growth of greenhouse gas emissions.

Dr Boer predicted that an annual spend of hundreds of billions of dollars would eventually be needed to avert potentially catastrophic changes in sea levels, weather patterns and water resources.

UN scientists say the world's total carbon emissions should peak within five to 10 years and then rapidly decline to avert the worst consequences of climate change.

Developing countries blame the industrial world for creating the problem and have demanded that wealthy nations trim emissions by at least 40% from 1990 levels by 2020, and by 80% to 95% by mid-century.