ALGIERS: Barack Obama's pledge to work to reduce emissions sharply by 2020 is a "huge signal" of encouragement to countries negotiating a new climate pact, the head of the U.N. Climate Change Secretariat said on Wednesday.

The US president-elect said on Tuesday the United States would engage vigorously in climate change talks when he is president, and he pledged to work to reduce emissions sharply by 2020, despite the financial crisis.

"I think that will have a very positive influence on the negotiations," Yvo de Boer, who heads the Secretariat, told Reuters in Algeria. "He indicated that he intends to show national and international leadership.

"I think that that statement will be seen as a huge signal of encouragement to the international community," he said in an interview on the sidelines of an African environment conference.

De Boer said US emissions of greenhouse gases stood at 14% above their 1990 levels but it was possible to get volumes down to that target within the deadline. He said: "I think its feasible. It's a challenge, but it's doable."

European nations have pushed the United States for years to show more leadership on climate change so that China and India, developing nations whose emissions are outpacing the developed world's, will follow suit.

The Democratic president-elect, who regularly criticized the Bush administration's attitude toward global warming, said his government would set strong annual targets that set the country on a course to reduce emissions to their 1990 levels by 2020 and cut them by a further 80% by 2050.

Under the Kyoto Protocol, 37 developed nations have agreed to cut emissions by 5 percent below 1990 levels by 2008-2012.

Members hope to finalize a new accord to follow Kyoto at a summit in Copenhagen in late 2009, but pressure for poor countries, who made no Kyoto commitments, to sign up to cuts is fuelling tensions between rich and poor groupings in the talks.

Poverty in Africa, where nearly three quarters of people rely on agriculture, means it is the part of the world least able to adapt to the severe weather changes forecast to be triggered by global warming, experts say.

"We really need to use the Copenhagen opportunity to design a regime that is more Africa-friendly," de Boer said.

"African nations have actually been quite modest in the negotiations so far. This meeting in Algeria provides an opportunity for 53 African countries to really develop a collective position and that will give them important negotiating strength in the process," de Boer said.

Asked if Obama's apparent sensitivity to climate questions and his own part-African heritage would help strengthen African involvement in the climate talks, de Boer replied: "I think you should ask Senator Obama this question. He's made it very clear he's first and foremost an American. But let's see how he develops his international policy.