* Finance, overshadows climate talks on rules for Paris accord
* New meeting set for Bangkok before end-year deadline
* Graphic at: https://tmsnrt.rs/2fTjA1w
By Alister Doyle Environment Correspondent
BONN, Germany, May 10 (Reuters) - Governments made slow progress on a "rule book" for a global climate accord after two weeks of talks ending on Thursday and agreed to a new round of negotiations to break a diplomatic logjam before a year-end deadline for a deal.
Disputes among the senior climate officials from about 180 nations in Bonn included how rich nations will raise finance to a pledged $100 billion a year by 2020 to help developing nations cope with rising temperatures and cut their emissions.
"We can't say failure. But overall we've been having slow progress," Gebru Jember Endalew, chair of the group of least developed countries, told Reuters. Poor nations are most vulnerable to more droughts, floods and rising sea levels.
Delegates agreed to hold an extra session in Bangkok from September 3-8 before environment ministers meet in Katowice, Poland, in December when the rule book for the Paris pact is due to be agreed.
The 2015 Paris Agreement set a sweeping goal of ending the fossil fuel era this century with a trillion-dollar shift towards cleaner energies such as wind or solar power to help limit a rise in temperatures.
But it was vague on the details, such as how to measure financial flows to developing nations and how countries will report and monitor curbs on greenhouse gas emissions and ratchet up national goals every five years to limit global warming.
"We have to be very, very clear that we have a lot of work in the months ahead and that we have to improve the pace of progress to achieve a good outcome in Katowice," Patricia Espinosa, the U.N. climate chief, told a news conference.
She said progress had been "satisfactory" in Bonn.
Writing the "rule book" - formally known as "implementation guidelines" - is the biggest test of the international commitment to the Paris Agreement since President Donald Trump said in June he will pull out, doubting that climate change has a human cause.
Elina Bardram of the European Commission said clear rules on curbing emissions, adapting to climate change and finance were vital in 2018 to bring the Paris agreement to life. But she said some elements were likely to need more time.
"We have to accept that not all the nitty gritty details can be agreed by Katowice," she said.
Luke Daunivalu, chief negotiator for Fiji which is presiding at the talks in 2018, also said of the rule book: "How thick or how thin ... is an open question at the moment. It will become a little clearer at Bangkok."
Current national pledges to curb emissions put the world on track for a warming of about 3 degrees Celsius (5.7 Fahrenheit) above pre-industrial times, far above a Paris goal of "well below" 2C (3.6F). (Reporting By Alister Doyle Editing by Hugh Lawson)
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