* Agenda for work on new global climate deal is adopted
* Agreement breaks week-long deadlock over procedure
* Urgent climate action needed to limit global warming
By Nina Chestney
BONN, May 25 (Reuters) - More than 180 countries agreed on an agenda for work on a new climate treaty by 2015 at United Nations climate talks on Friday, breaking a week-long deadlock over procedure.
"(The work plan) was not an easy issue to agree (on)," U.N. climate chief Christiana Figueres told reporters after the negotiations held at Bonn in Germany.
"All parties needed reassurances from each other to allow them to undertake the work with a certain sense of comfort."
U.N. climate talks in South Africa last year agreed a package of measures that would extend the 1997 Kyoto Protocol after it expires at the end of this year and decide a new, legally binding accord to cut global greenhouse gas emissions by 2015, coming into force by 2020.
In the Bonn talks, the first negotiation session since that deal was struck, delegates have argued for over a week on how to organise work on a new climate deal and appoint a chair to steer the process.
Procedural wrangling during the two-week session showed that deep disagreements remained among participants and put a lot of pressure on talks in Doha, Qatar, at the end of the year to deliver, observers said.
"When people start fighting about agendas it is a symptom of lack of trust and of some pretty substantive areas of disagreement," said Celine Charveriat, director of advocacy and campaigns at international development charity Oxfam.
Countries will still need to work more on some critical issues, including the length of an extension of the Kyoto Protocol, which nations will sign up to it and the level of emissions cuts that they will pledge.
They also need to identify ways to raise $100 billion a year of finance by 2020 to help developing countries tackle climate change.
Green groups and nations most vulnerable to the effects of global warming warn time is running out to avert disastrous consequences like increased extreme weather, ocean acidification and melting glaciers.
Countries have agreed that deep emissions cuts are needed to limit a rise in global average temperature to less than 2 degrees Celsius this century above pre-industrial levels, a threshold that scientists say is the minimum required to avert catastrophic effects.
However, one of the main contributors to climate change, global carbon dioxide emissions, hit a record high last year, according to the International Energy Agency, which advises industrialised countries.
Some countries also look set to miss their emissions cut targets for 2020, putting the world on a dangerous trajectory towards a rise in global average temperature of 3.5 degree Celsius, research showed on Thursday.
"The majority of countries want to move forwards faster but..a relatively small group is holding up what the rest of the room wants," said the European Union's chief negotiator Artur Runge-Metzger. (Editing by Anthony Barker)