By Richard Black
Environment correspondent, BBC News website
Prince Charles aims to build a dialogue on rainforest conservation
The UK government is hoping to bridge some difficult divides over tackling climate change at a meeting in London.
The Major Economies Forum (MEF) brings together 17 of the world's biggest greenhouse gas-emitting countries.
The meeting on Sunday and Monday will aim to make progress on protecting forests and providing finance to help poor countries adapt to climate change.
Ministers hope that these discussions will increase chances of agreeing a new climate treaty at December's UN summit.
In recent days there have been a number of warnings that progress is stalling, with Rajendra Pachauri, head of the Intergovernmental Panel on Climate Change, telling Newsweek magazine that "the prospects that states will actually agree to anything in Copenhagen are starting to look worse and worse".
But noting that the summit was only 50 days away, UK Energy and Climate Secretary Ed Miliband declared: "We are determined to throw everything at it and go all out to get a deal in Copenhagen; and MEF is part of that deal."
Energy Secretary Ed Miliband: ''We have all got to respond to make the deal happen''
MEF was established by President George Bush and brings together developing countries such as as China and India, and industrialised nations such as the US, UK, France and Japan.
Six other developing countries, including some of the world's poorest such as Ethiopia, are invited for the first time.
On Sunday evening, Prince Charles will host a dinner at which ideas for financing forest protection in developing countries will be discussed.
MEF is not part of the formal UN process and so firm commitments are unlikely to come from the meeting.
It is seen instead as a forum where countries can explore options and positions in a less pressured environment.
Referring back to the last set of preparatory UN talks that ended in Bangkok just over a week ago, Mr Miliband said progress had been made but much remained to be agreed.
He praised a number of developing countries including China, India and Indonesia for recent pledges or proposals on restricting the growth of their greenhouse gas emissions.
Many campaign groups say the UN talks are stalling
China's President Hu Jintao pledged at the UN General Assembly last month to increase energy efficiency.
India has set targets on fuel efficiency, renewables and forest protection if western nations agree to major greenhouse gas reduction targets, while Indonesia has said it will reduce the growth in its greenhouse gas emissions by 25% from a "business-as-usual" trajectory.
"The actions that China and India are taking to 2020 are essential to a successful outcome," Mr Miliband said.
"President Hu made an important step forward... (but) he hasn't yet put numbers on Chinese action and it's important that Chinese action is quantified in terms of numbers."
Environmental groups say the ball is now in the court of richer nations - to pledge more ambitious cuts than they have so far, and to provide sums of money that can help developing countries adapt to impacts of climate change.
"The rich countries of the Major Economies Forum must urgently put new money on the table to ensure the developing world can grow cleanly and adapt to the effects of climate change which are already putting millions of lives at risk," said Friends of the Earth International climate campaigner Asad Rehman.
UK Prime Minister Gordon Brown has proposed setting up a fund that would raise and disburse $100bn per year, while there is a lot of interest in a Mexican proposal that would see money levied from industrialised countries and some of the richer developing nations on a flexible sliding scale.
Issues over how such funds should be governed have partially been resolved. Developing countries have fought long and hard to keep control away from the World Bank; and support is emerging for a consensus that would see the UN climate convention in overall charge of the money, with the World Bank running the fund's practicalities.
But much remains to be agreed, including the fundamental issue of how much adaptation money should be raised from public funds and how much from levies on the proposed global carbon market.
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