U.N. climate talks blocked as nations battle over finance WARSAW (Reuters) - Talks to lay the foundations for a new U.N. climate pact due in 2015 were deadlocked as they ran into overtime on Saturday, with nations at odds over stepping up finance for developing countries to ease the impact of global warming. The Warsaw meeting, which had been due to end on Friday, was meant to lay the groundwork for creating the first climate accord to be applicable to all nations by 2015, which would come into force after 2020. However the only concrete measure to have emerged was an agreement on new rules to protect tropical forests, which soak up carbon dioxide as they grow. Nearly 200 countries assembled at the U.N. conference have stumbled over three major issues over the past two weeks: the level of emissions cuts, climate finance and a "mechanism" to help poor countries deal with loss and damage from global warming. Climate change talks are still on knife edge after a long night. A few countries (are) insisting on looking backwards. Could be a long day," British Energy and Climate Change Minister Edward Davey said on Twitter. It also suggested they report every two years on their approaches to stepping up finance levels to $100 billion. A group of developing countries and China were in favor of an amendment to the text that "at least $70 billion" a year of climate finance is committed from 2016. The talks have also proposed a new "Warsaw Mechanism" which would provide expertise, and possibly aid, to help developing nations cope with loss and damage from extreme events such as heat waves, droughts and floods, and creeping threats such as rising sea levels and desertification. Developing nations have insisted on a "mechanism" - to show it was separate from existing structures - even though rich countries say that it will not get new funds beyond the planned $100 billion a year from 2020. A text on Saturday said that all nations should "initiate or intensify" their domestic preparations for "intended nationally determined commitments" and have them ready by the end of the first quarter of 2015, if they could. The European Union is among countries which want pledges in 2014. "It's not everything we wanted, but we know there are some issues we cannot solve here," Pete Betts, lead negotiator for the European Union, told delegates. Meanwhile, many developing nations want to see more urgency. Typhoon Haiyan in the Philippines, which has killed over 5,000 people, has put the spotlight on extreme weather. It also said that "sustained and substantial" cuts in greenhouse gases were needed to achieve a U.N. goal of limiting warming to manageable levels. "We have compromised on many issues, but there is a limit for compromise by the most vulnerable countries of this planet," said Nepal's Prakash Mathema, chair of the group of least developed countries. Additional reporting by Susanna Twidale and Stian Reklev; Editing by Pravin Char