U.S. Secretary of State Hillary Clinton said the United States is prepared to work with other countries to fund $100 billion a year by 2020 to address climate change needs of developing countries. 

African Union Commissioner for Rural Economy and Agriculture Rhoda Tumusiime said Clinton's comments are a positive step.  Tumusiime spoke to VOA from Copenhagen, where she said she feels talks are making progress.

"I am not 100 percent hopeful, but at least I am really hopeful that something can be worked out that is very positive," she said.

Delegates have been in Copenhagen for 10 days with many observers saying the summit is making slow progress.  The main stumbling blocks for a global climate change deal have been targets for cuts to greenhouse gas emissions and financial assistance for poor countries.

African negotiators briefly walked out of the climate talks Monday, angered by what they consider efforts to sideline poor nations and weaken support for a binding deal. 

But Wednesday several African countries scaled back the amount of money they say will be necessary to cope with climate change, in an effort to help move the talks to an agreement.

Friday, the final day of talks, U.S. President Barack Obama is expected to arrive and Tumisiime says she thinks this will push talks forward. 

"The major decision makers, the high-power people are coming in tonight and tomorrow.  So mainly tomorrow, that is when the decisions are going to be made," Tumisiime said.

U.S. climate specialist Ilana Solomon of the international aid group Action Aid, says it is up to Mr. Obama to ensure the Copenhagen conference ends with a strong climate deal.

"If Obama were to come to Copenhagen with more ambition than we have already put on the table for mitigation and with a clear number for our contribution to public finance, we think this could make a huge impact," she noted.

U.S. emissions reduction targets and commitments to financing must be supported by the U.S. Congress - an obstacle that political analysts say may be difficult to overcome.  But Soloman says Mr. Obama must make specific financial pledges.

"I mean we have seen presidents all the time in the past make commitments to finance, be it for food security or HIV/AIDS without Congressional action," she added.  "So I think it is this kind of risk taking and leadership that we really need to see at this moment."

Meanwhile, the EU Commission says it will provide around $75 million to help countries in the Horn of Africa, who are right now suffering from drought caused by climate change.