Negotiators locked horns Friday over the extent to which wealthy nations should bankroll ambitious targets for reversing the loss of Earth\'s dwindling natural resources. Just days after 400 plants and animals were added to a \"Red List\" of species at risk of extinction, ministers from more than 80 countries are set to conclude biodiversity talks in the southern Indian city of Hyderabad. UN countries agreed at a conference in Japan in 2010 to reverse by 2020 the worrying decline in natural resources that humans depend on for food, shelter and livelihoods. But the 20-point plan has been hamstrung by a lack of money for conservation efforts at a time of global financial austerity. After bargaining late into Thursday night, environment ministers spent Friday huddled in separate groups behind closed doors on the second floor of a conference centre in Hyderabad in a bid to break the deadlock. \"Looking like another long evening in Hyderabad as talks on resources continue,\" tweeted European Commissioner for Environment, Janez Potocnik. \"It\'s not looking like the final deal will be very ambitious,\" said Lasse Gustavsson, WWF International\'s executive director of conservation. \"But we are expecting talks to go on late into the night, so there\'s still a chance some progress will be made.\" A closing plenary session started nearly two hours late to adopt other decisions as financial negotiators were absent, still in closed talks. Delegates likened the talks to a game of poker. \"At this point, it is a matter of who blinks first,\" said one. Parties mostly agree that rich nations\' funding of poor countries\' biodiversity efforts should double. Richard Benyon (centre) addresses local political leaders and Indian farmers in Warangal district © AFP Noah Seelam The disagreement is: from when, for how long, and what measures the developing world will agree to in return -- like reporting on their biodiversity spending and preparing national plans. India, backed by a group of developing countries, proposed on Friday that the aid must be doubled from 2015 -- five years earlier than the original draft proposal. Held under the auspices of the UN Convention on Biological Diversity (CBD), the Hyderabad meeting is meant to come up with tangible ways to execute what have become known as the Aichi Biodiversity Targets. They include halving the rate of habitat loss, expanding water and land areas under conservation, preventing the extinction of species on the threatened list, and restoring at least 15 percent of degraded ecosystems. A quarter of the world\'s mammals, 13 percent of birds, 41 percent of amphibians and 33 percent of reef-building corals are at risk of extinction, according to the International Union for Conservation of Nature\'s \"Red List\", updated on Wednesday. Estimates vary, but experts say hundreds of billions of dollars will be required to achieve the targets set in Japan. The money agreed on Friday should be spent on improving and expanding conservation areas, training and scientific research. It could also help poor countries cut subsidies for practices that harm the environment, such as overfishing, replacing these with grants that support green projects instead. The ministerial section of the talks, which opened on Wednesday, comes at the tail-end of two weeks of tough negotiations by senior bureaucrats from 184 CBD parties. The plenary, which will reconvene later Friday, hopefully to adopt a financial agreement, approved a bid by South Korea to host the next CBD meeting, to be held in 2014. The convention, to which 193 countries are signatories, marks its 20th anniversary this year. It has already missed one key deadline when it failed to meet the target set to halt biodiversity loss by 2010.