* Coral, sea levels seen vulnerable even with slight warming
* IPCC to study risks of 1.5 degree Celsius warming
* V20 developing nations urge more action for 1.5C ceiling (Adds vulnerable nations' resolution in Washington)
By Alister Doyle
OSLO, April 14 (Reuters) - The U.N.'s panel of climate scientists agreed on Thursday to study how to limit global warming to the toughest target suggested by world leaders, saying even small rises in temperatures could be harmful.
The panel would look into ways to restrict the rise in temperatures to 1.5 degree Celsius (2.7 Fahrenheit) above pre-industrial times after a 195-nation summit in Paris agreed in December to try and phase out net greenhouse gas emissions this century.
Hoesung Lee, chair of the U.N.'s Intergovernmental Panel on Climate Change (IPCC) said there were "serious risks" with even minor rises in temperatures from current levels, for instance to coral reefs and to coasts from rising sea levels.
"There was not much scientific research on this topic" when the IPCC last issued a major overview of the risks of global warming in 2014, he told a webcast news conference from Nairobi.
The IPCC would issue the 1.5C report in 2018 and two other special climate reports in coming years, one on land, desertification and food security and another on oceans and the world's icy areas, he said.
The December 2015 summit asked the IPCC to come up with a report about 1.5C, a level scientists reckon would demand drastic cuts in greenhouse gas emissions..
In Washington, finance ministers from a group of developing countries vulnerable to climate change, from Afghanistan to Yemen, urged developed nations to make the global financial system more compatible with the 1.5C goal.
"We see the financial system as a weapon to fight climate change with tremendous potential," Cesar Purisima, secretary of finance of the Philippines and head of the Vulnerable 20 (V20) group, said in a statement.
The V20 said its members planned to adopt domestic carbon pricing systems within 10 years and called for an international tax on financial transactions to help fund efforts to slow climate change and adapt to rising temperatures.
Last year, average global surface temperatures hit the highest since records began in the 19th century, about 1C above pre-industrial times.
Lee said the IPCC would also issue an overall report about the risks of climate change in 2022, in time for a scheduled global review in 2023 of governments' plans for fighting climate change. (Reporting By Alister Doyle, editing by Pritha Sarkar, Larry King)