The former US vice-president Al Gore and the UN climate change panel will share the 2007 Nobel peace prize for raising awareness of the risks of climate change, the Nobel committee announced today.

Chosen from a field of 181 candidates, Mr Gore and the UN's intergovernmental panel on climate change (IPCC) will split the $1.5m (£750,000) prize.

The Norwegian committee praised Mr Gore for his strong commitment to the struggle against climate change.

Mr Gore responded by telling a press conference that climate change was the "most dangerous challenge we've ever faced".

"I will be doing everything I can to try to understand how to best use the honour and recognition of this award as a way of speeding up the change in awareness and the change in urgency," Mr Gore said.

"It truly is a planetary emergency: we have to respond quickly. I'm going back to work right now. This is just the beginning."

Mr Gore, who lost the 2000 presidential election to George Bush, ignored questions on whether he planned to run again for president.

The Norwegian committee said Mr Gore was "probably the single individual who has done most to create greater worldwide understanding of the measures that need to be adopted".

However, Mr Gore's award-winning film on the issue, An Inconvenient Truth, was this week criticised in a British high court case for allegedly containing inaccuracies.

Mr Gore said he would donate his share of the prize money to the Alliance for Climate Protection, a group seeking to change public opinion in the US and around the world about the urgency of dealing with climate change.

"I am deeply honoured to receive the Nobel peace prize," Mr Gore said in an earlier statement.

"This award is even more meaningful because I have the honour of sharing it with the IPCC - the world's pre-eminent scientific body devoted to improving our understanding of the climate crisis - a group whose members have worked tirelessly and selflessly for many years."

The Nobel committee said the IPCC had created an ever broader, informed consensus about the connection between human activities and global warming.

"Thousands of scientists and officials from over 100 countries have collaborated to achieve greater certainty as to the scale of the warming," the panel said. "Whereas in the 1980s global warming seemed to be merely an interesting hypothesis, the 1990s produced firmer evidence in its support."

The Nobel committee said that by awarding the prize to the IPCC and Mr Gore, it wanted to bring a sharper focus on the processes and decisions needed to protect the world's future climate.

"Action is necessary now, before climate change moves beyond man's control," the panel warned.

The joint award to Mr Gore, who was the favourite among the contenders, is expected to galvanise his supporters, who are pushing him to run again for the White House, despite his loss eight years ago.

Since then, Mr Gore has appeared more relaxed, shedding an uptight image that did him no favours in contrast to Mr Bush, who projected an easygoing charm.

Should Mr Gore take the plunge, he can count on strong grassroots support, though his detractors believe that, in the glare of presidential politics, he will revert to his old, wooden self.

The "draft Gore" movement has been gaining momentum, accumulating about 127,000 signatures this year, 10,000 of them in the last week of September alone.

Mr Gore has consistently said he is not interested in running again for the White House, insisting he can be more effective in the fight against climate change outside mainstream politics.

But his denials of interest have done little to dampen the enthusiasm of supporters, who feel that as president he would have the credibility required to push through tough measures to slow climate change.

The other presidential candidates - Hillary Clinton, in particular - have so far disappointed environmental activists by shying away from promising aggressive action to deal with America's contribution to climate change.