As negotiations over a new global climate agreement entered its second full day in Paris on Wednesday, developed countries showed their reluctance to scale up finance support to developing countries after 2020 from a base level which they promised years ago.

The spirit of unity and solidarity expressed by some 150 world leaders including those from the richest ones at the opening day of Paris climate conference was yet translated into concrete actions on negotiating tables.

Developed countries continued to ignore calls from developing countries to scale up their finance support after 2020, when the new agreement comes into force, from a floor of 100 billion U.S. dollars per year, a level the developed countries promised in 2009 to reach by 2020.

While admitting the importance of providing finance support to developing countries, developed countries attempt to use vague language in the agreement, refusing to put any figure on the money they are willing to provide.

"That is a live and open conversation," said United States Special Envoy for Climate Change Todd Stern, adding that his country agreed the notion of "robust financing" in post-2020 period, not mentioning how much this "robust" finance will be.

"Right now, they are not (willing to accept the notion of 100 billion U.S. dollars). They are pushing back against this and not wanting to have that language in the agreement," said Alden Meyer, strategy and policy director for the Union of Concerned Scientists.

European Union also shied away from the 100-billion-U.S-dollar figure. Its delegation head Sarah Blau just told reporters that the finance support after 2020 will based on "what we have done pre-2020".

What the developed countries have done, however, is far from reaching its promised target.

According to calculations of World Resources Institute, only 17 billion U.S. dollars were provided from developed countries public funds in 2012. The Green Climate Fund, a foundation expected to be a major financing entity under the Paris agreement, received only 10 billion U.S. dollars pledges currently. Less than 60 percent of them were actually delivered.

"Paris deal is about responsibility, it's about obligation. Majority of developed countries who caused this problem (of climate change) are obliged to pay money. They are not doing it," said Harjeet Singh of ActionAid.

Finance is one of the most challenging issues in climate negotiations and was expected to be resolved by government ministers at final moments of the two-week conference. On Wednesday, G77 and China, a group representing 134 developing countries, urged developed countries to meet their obligations under the Paris agreement.

"The Paris outcome must provide clarity on the level of financial support that will be provided by developed country Parties to developing country Parties," said the group in a statement. "This is a legal obligation under the Convention. It is neither 'aid' nor 'charity', nor is it the same as development assistance."