U.S. President Barack Obama is scheduled to arrive in Copenhagen on Thursday night and will join the UN climate talks on Friday, bringing hopes to finish a complicated process of reaching a political agreement to reduce greenhouse gas emissions and fight global warming.

The President has been making phone calls to other world leaders this week to discuss the process before his arrival.

His presence and contribution could be a potential deal-maker to overcome persistent disagreements between developed and developing nations.

The US Secretary of State Hillary Rodham Clinton said at the conference by quoting a Chinese proverb when you are in a common boat, you have to cross the river peacefully together, and we are in this boat together.

Clinton said she believed there was still a way forward for the negotiations, and she announced that, if an agreement was reached, the U.S. would work with other countries toward a goal of jointly mobilizing $100 billion per year to help address the needs of poor and developing countries coping with climate change.

The U.N. Climate conference started two weeks ago in Denmark hoping to craft a comprehensive framework to curb the greenhouse gas emissions that cause global warming and provide funds for poor countries to deal with climate change.

They wanted to get agreement on all the main elements so that a treaty could be signed next year.

But so far the talks have been marked by sharp disagreements between China and the United States and a big chasm between rich and poor nations over what should be done.