As world leaders gather in New York for the opening of the 63rd session of the United Nations General Assembly, they face a double challenge. As well as the UN’s commitments to maintaining world peace and reducing poverty, they must take urgent action to fight the financial crisis enveloping world markets.

Keynote speakers include US President George W. Bush and French President Nicolas Sarkozy, speaking on behalf of the European Union. Western nemeses such as Iranian President Mahmoud Ahmadinejad, Zimbabwean leader Robert Mugabe and Venezuelan firebrand Hugo Chavez will also speak.

Bush, who will address the assembly for the last time as US president, is expected to talk about his recent decision to push a 700 billion dollar financial bailout plan through Congress.

"We are so intertwined with other economies around the world in our increasingly global economy, that of course the United States’ economy is going to be a topic," White House spokeswoman Dana Perino said.

Other topics likely to top the agenda are the withdrawal of Russian troops from Georgia and nuclear-development efforts in Iran and North Korea.

Saving the world financial system versus saving Africa

“The General Assembly this year was going to be all about fighting poverty,” says FRANCE 24’s UN correspondent, Philippe Bolopion.

In 2000, the UN voted to endorse a series of ambitious commitments known as the Millennium Development Goals to reduce poverty in Africa. UN Secretary General Ban Ki-moon recently reiterated the importance of this pledge, which would require an estimated 72 billion dollars a year in external funding until 2015 in Africa alone.

But donors have already fallen behind their commitments, sowing resentment among African leaders, Bolopion explains.

“They say 'Look, in 2005 in Gleneagles, we were promised 20 billion dollars to fight poverty and rich countries could never find that money. And now they find 700 billion dollars to save the financial system in the US.' So they fear that the developed countries are not really serious about fighting poverty.”

A summit meeting on implementing the goals is scheduled for Thursday on the sidelines of the General Assembly.

A vital but evolving institution

The changing role of the multilateral institution explains some of the tensions. As the number of member states – now 180 – grew through decolonization and the dismantling of the former Soviet Union, the UN – and the General Assembly that is its main forum – has become increasingly complex.

“The mere existence of the organization is not sufficient to achieve the goals that were set out for it in 1945,” warns Paul Vallet, an assistant professor at the American Graduate School of International Relations.

Demands for UN peacekeeping intervention have exploded in recent decades, but the UN’s authority is being increasingly questioned by some of its members.

UN diplomats said they expected a flurry of meetings over calls by the African Union and the Arab League to defer any prosecution of Sudanese President Omar al-Bashir on Darfur genocide charges.

“Developing nations are extremely reticent to see the UN move on this matter and try to challenge the legitimacy of these leaders,” said Vallet.

Vallet added that after years of strained relations between the United Nations and the United States, the UN’s biggest contributor, the American view on the UN is shifting. "As an institution," he said, "the UN remains the greatest legitimacy-provider for a number of missions the US would like to see on the agenda."