The top climate-change negotiator from the United States applauded China on Tuesday for its $3 billion contribution to help developing countries respond to climate change.

China announced the contribution in September during President Xi Jinping's state visit to the US. It was a big increase over previous commitments and one that could potentially surpass the US contribution to the United Nations' Green Climate Fund.

"That's terrific. So, in a system going forward, as more and more countries grow, develop and gain the capacity to become contributors－not just recipients－we think that that's a development that should be encouraged," said Todd Stern, US President Barack Obama's special envoy for climate change, in a conference call from Washington with media about the Paris climate change conference.

Obama is due to meet with Xi and Indian Prime Minister Narendra Modi on the first day of the Paris talks on Monday to give momentum to the negotiations, White House officials said on Tuesday. Those meetings, at the start of the two-week summit, will "send a strong message to the world about their strong commitment to climate change", White House Deputy National Security Adviser Ben Rhodes said.

Paul Bodnar, senior director for energy and climate change on the National Security Council, a White House advisory body, said Obama's meetings with Xi and Modi are not meant to yield announcements but are to consult on key issues in the negotiations.

"These two countries are two of our most important partners in dealing with global climate change," he said.

Joanna Lewis, associate professor of science, technology and international affairs at Georgetown University, Washington, D.C., said in an interview that the mere announcement of China's financial contribution is a "big deal, because up until this point the financing discussion has been limited to developed countries providing funds for developing countries". She said the contribution "broadens the scope of climate finance as well as the total amount that countries will pledge".

Financing climate goals has been a key issue leading up to the Paris talks, with countries discussing how to unlock money to help developing countries achieve low-carbon growth.

There are other questions on how to transition the broader global economy toward low-carbon development and how to balance public and private support, according to climate experts and organizations.

Stern also addressed a question on the role developing countries have to play in climate negotiations when developed economies like the US are often the largest emitters. He cited China as an example of a developing country, but also one that has been active in its contributions to climate action.

"So the question is actually perfectly apt, because the United States is the second-biggest emitter. And the biggest emitter is China. China is a developing country in the context of climate negotiations, and that's just an illustration of why we need to have both sides of this equation acting," he said.

Representatives from about 200 countries will gather in Paris next week to put together a global agreement cutting greenhouse gases. At a similar meeting in 2009 in Copenhagen, countries failed to reach agreement on how best to achieve global climate goals.