LONDON (Reuters) - Countries which agreed to sign a deal in 2015 to cut greenhouse gas emissions should set milestones this year to ensure the necessary work is done on time, the United Nations’ climate chief said on Wednesday.

Last year’s U.N. climate talks in Durban, South Africa, agreed a package of measures which would eventually force all the world’s polluters to take legally binding action to slow the pace of global warming.

Delegates agreed on the so-called “Durban Platform for Enhanced Action” - a process to develop a new protocol, legal instrument or legally binding deal by 2015 which would apply to all parties under the U.N.’s climate convention and would come into force no later than 2020.

But a clear timetable and targets for this process have not yet been set.

“Parties need to think between now and Doha how they want to organize their work between now and 2015 and how they will move towards that legal agreement,” Christiana Figueres, executive secretary of the U.N.’s Framework Convention on Climate Change told the Reuters Global Energy & Environment Summit.

“My hope is they will establish milestones along the way so they are able to measure their progress.”

U.N. climate talks are currently taking place in Bonn, Germany until May 25. More talks are expected in South Korea in the autumn and in Doha, Qatar, at the end of this year.

A working group on the Durban Platform will be launched later this week at the Bonn talks.

“How they want to do that (set milestones) might be more for the end of this week once we hear the first statement from (the group),” Figueres added via conference call at the Reuters summit in London.

FUND

Other issues to be discussed in Bonn and in Qatar at the end of this year include how to implement an extension to the Kyoto Protocol and how long that will last; how to raise ambition on emissions cut pledges, and raising long-term finance to help more vulnerable countries adapt to the harmful effects of climate change.

The Durban climate talks agreed on the design of a Green Climate Fund, which should help channel up to $100 billion a year by 2020 to developing countries most affected by climate change.

The fund is still empty, although discussion of ways to fill it are ongoing, Figueres said.

Many countries, including the European Union, have yet to come up with a plan to provide long-term climate financing, against the backdrop of globally depressed economies and the euro zone crisis.

Financing the fund cannot happen until its board is constituted and that is still being decided, after more countries applied for board seats than are available.

“Not until we have the full board nominated can we go forward on programming and planning the first board meeting,” said Figueres.

“There is more enthusiasm than seats. The challenge is to fit (countries) around the table.”

The first board meeting is scheduled for May 31 but a delay seems increasingly likely if the board is not agreed soon.

“We would highly welcome being able to respect the current dates for the board but it makes no sense to call for a board meeting before all countries have agreed how it is going to be constituted,” she said.

“We will know within next few days how likely that going to be.”

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