Paris: US emissions of greenhouse gases are poised to rise by nearly a quarter over a key UN benchmark by 2025,the date set by President George W Bush for stabilising this pollution, an International Energy Agency (IEA) expert said today.

The benchmark of 1990 is a closely watched -- and politically sensitive measure of commitment for tackling global warming.

"With current policies, the greenhouse-gas emissions of the US will increase by 18 per cent between 2005 and 2025," IEA chief economist Fathi Birol told AFP.

"If you compare this with 1990 levels, by 2025 there will be plus 38 per cent.

He added: "If the (newly announced) policies and measures -- energy efficiency, renewables, all the policies -- are implemented, you can take off about 15 per cent from this."

"So it means an increase of about 23 per cent between 1990 and 2025,but only if the policies are implemented and respected."

Bush's plan ran into fire at a meeting of major emitters in Paris yesterday and today, where some countries lashed it as falling way short of what was needed.

The European Union has promised to cut its own carbon pollution by 20 per cent by 2020 compared with the 1990 level, and offered to deepen this to 30 per cent if the United States and other rich economies follow suit.

UN scientists last year sketched a target of cuts of 25-40 per cent by advanced economies by 2020.

Source : PTI