Britain has to work with the rest of the world in tackling climate change, Energy Secretary Ed Davey told ITV News, after a major report highlighted the "severe risks" of rising temperatures.
Mr Davey said: "It shows how urgently we have to act. It needs far greater political will, even in the UK from some political parties, but it needs that political will to be shown around the world".
The Prince of Wales's Corporate Leaders Group, which represents businesses ranging from BT to Thames Water, Shell, EDF and Unilever, called on governments to set ambitious global climate targets.
Philippe Joubert, chairman of The Prince of Wales's Corporate Leaders Group, said:
Many businesses, such as those represented in the Corporate Leaders Group are already investing in a low-carbon future.
But if we are to unlock the scale of change that we need, we must have a level of policy clarity equal to this scientific clarity.
Governments need to pay attention and phase out coal and oil now or end up doing it later at a much higher cost, Greenpeace's head of international climate politics has said, after a major report highlighted risk of climate change.
For scientists, there is nothing vague about how to deal with climate change.
[Those] who seize the potential of renewable energy will leap ahead to a sustainable future.
Climate change is happening, it is almost entirely man's fault and limiting its impacts may require reducing greenhouse gas emissions to zero this century, the UN's panel on climate science has said.
UN Secretary-General Ban Ki-moon, who was at the news conference, stressed that "if we act now, immediately and decisively we have the means to build better and more sustainable world.
He later said: "Inaction of climate action will cost much, much more. This climate action and economic growth are two sides of just one coin".
We must act on climate change now, the Energy Secretary has said, after the publication of a major report on climate change.
Ed Davey, said: "It sends a clear message that should be heard across the world - we must act on climate change now.
"It's now up to the politicians - we must safeguard the world for future generations by striking a new climate deal in Paris next year."
The scientific case for prioritising action on climate change was clearer than ever, the chairman of the Intergovernmental Panel on Climate Change (IPCC) told a conference, after a new UN report was published.
We have little time before the window of opportunity to stay within 2C of warming closes.
To keep a good chance of staying below 2C, and at manageable costs, our emissions should drop by 40% to 70% globally between 2010 and 2050, falling to zero or below by 2100.
We have that opportunity, and the choice is in our hands.
Power generated from fossil fuels should be phased out completely by 2100 a new report has warned.
The United Nations climate body published the final report of its latest assessment on the science of climate change, drawing together three studies published in the past year.
In the majority of low?concentration stabilization scenarios, the share of low?carbon electricity supply (comprising renewable energy (RE), nuclear and Carbon Capture Schemes (CCS), including BECCS) increases from the current share of approximately 30% to more than 80% by 2050, and fossil fuel power generation without CCS is phased out almost entirely by 2100.
The report comes as efforts build towards securing a new global treaty on climate change, which it is hoped can be agreed in Paris at the end of next year, and it said that international co-operation was "critical" for effective efforts to tackle the problem.
Kofi Annan has said that developed countries had failed to respond to the crisis until it reached their shores.
The former UN secretary general told the BBC's Newsnight:
I am bitterly disappointed by the response. I am disappointed in the international community for not moving faster. In this world we are in it together.
If the crisis had hit some other region it probably would have been handled very differently. In fact when you look at the evolution of the crisis, the international community really woke up when the disease got to America and Europe. And yet we should have known that in this interconnected world it was only a matter of time.
I point the finger of blame at the governments with capacity ... I think there's enough blame to go around. The African countries in the region could have done a bit more, they could have asked for help much faster and the international community could have organised ourselves in a much better way to offer assistance. We didn't need to take months to do what we are doing today.
Victoria Beckham was the new face on the United Nations stage in New York today.
The pop star turned UN goodwill ambassador talked about the plight of babies born with the HIV virus in South Africa.
ITV News' Rebecca Barry reports: