Chancellor Alistair Darling has urged finance ministers from the world's leading economies to "get on" with tackling climate change.
Speaking ahead of the G20 meeting, which begins in St Andrews on Friday, Mr Darling said climate change was a "present problem" which needs billions of pounds of funding from governments across the globe in order to be tackled.
He said: "We either take action and stop those problems happening or we fail to take action and we face bigger costs down the line.
"My message to my fellow finance ministers is there's a job of work to be done here. I don't think anyone seriously denies there's a problem here. Let's get on with it."
The Chancellor, who is hosting a meeting of G20 ministers at the summit, stressed that "heavy lifting" was needed to make progress on the issue.
And despite the current financial turmoil, Mr Darling said investing in the fight against global warming was crucial.
He added: "People, not just in governments throughout the world but, more importantly, people in countries around the world, want us to be actually taking action now to deal with a present problem - that's the damaging effects of climate change.
"So there's a lot of work to be done still, a lot of heavy lifting, a lot of arguments still to be won but that's an important part of this weekend."
Last week, EU leaders agreed to a 100billion euro - £89.6billion - annual package of public and private finance by 2020 to help poorer nations develop green industries and adapt to climate change.
Environmental group WWF is urging ministers to agree to an immediate $10billion - £6billion - a year to help the most vulnerable countries adapt to changing climate.
The WWF also says a larger $160billion - £96billion - deal should be struck to help reduce harmful emissions.
The talks, which will last until Saturday, are the last in a series which saw leaders agree a one trillion dollar "fiscal stimulus" plan in the wake of global recession.
A small band of around a dozen students gathered on Friday to demonstrate as the summit got underway.
Colleen Roberts, 21, an international relations student at St Andrews, said: "Our representative democracy is failing us and we need to take action.
"Our politicians should see what people are feeling."
Ms Roberts, who is from Wrexham, Wales, added: "The turnout here doesn't surprise me. People don't vote, they don't make themselves heard."
Amir Gholami, 33, from Luxembourg and studying at St Andrews, said: "I think the people at the G20 are representative of a system that is part of the problem not the solution."
Larger demonstrations are planned for Saturday.
Last updated: 06 November 2009, 13:58
The links provided allow you to bookmark this page into your favourite social media website. For users with JavaScript disabled copy and paste the URL from the address bar into your chosen social bookmarking site.