On the agenda as both the UN General Assembly and the Security Council convene in New York City are issues ranging from climate change and hunger to nuclear proliferation and structural reform of the institution itself.

One of the highlights will be Barack Obama's address to the 192-member Assembly on Wednesday, his first speech to that body since becoming US President.

"I hope we can demonstrate that the United Nations does not have to be just a diplomatic talkshop on First Avenue," US Secretary of State Hillary Clinton said in advance of Obama's address.

Experts anticipate that Obama will put a clear end to his predecessor George W. Bush's disregard toward the UN as a means of multinational cooperation.

"We expect there will be a new position from the US vis-à-vis the United Nations and that relations will be much more constructive than under Bush," Sven Bernhard Gareis, Professor of Political Science at the University of Muenster, told Deutsche Welle. "As the leader of the world's most powerful nation, he won't allow himself to be constrained, but he will come out in favor of the principle of multilateralism."

But Obama's efforts to turn US policy may be hindered by the man following him on the podium in New York, Libyan President Muammar Gadhafi. He is making his first visit to the UN in his 40-year rule.

Controversy brewing?

Libya holds the General Assembly's rotating presidency and also currently sits on the UN Security Council as a non-permanent member.

As a head-of-state accused of sponsoring terrorism in the past, Gadhafi is hardly the obvious choice for the role of international mediator. And the hero's welcome recently given in Libya to the mastermind of the 1988 Lockerbie plane bombing, after he was released from a British prison, hardly assuaged skeptics.

Nonetheless, some experts say Libya - and its leader - can play a constructive role in international dialogue.

"The fact that Libya can take over such an office is part of the normal functioning of the world," Gareis said. "There was a lot of protest when Libya took over the UN human rights commission in 2003, but they did the job in orderly fashion. That was a sign that Libya has begun to abide by international rules."

Since the late 1990s, Libya has pursued a course of reconciliation with the West. Gadhafi has consistently opposed al Qaeda, and in 2003, Libya began dismantling its weapons of mass destruction program.

But as the past has shown, the Libyan leader is often good for surprises.

"Gadhafi is predictably unpredictable, so I think we'll see a lot that's unexpected and a lot of provocation," Isabelle Werenfels, a North Africa expert at the German Institute for International and Security Affairs, told Deutsche Welle. "There could be a lot of suggestions that are - to put things diplomatically - controversial."

For that reason, Obama advisors reportedly have been working behind the scenes to ensure the UN's scheduling doesn't make the US President and the Libyan leader appear too chummy.

Nuclear disarmament restart

But Obama and Gadhafi will encounter one another again at the UN Security Council on Thursday. Obama is set to become the first US President to chair a summit of this body and all of the 12 heads of state are expected to attend.

The Security Council gathering, which will focus on nuclear non-proliferation and disarmament, could be the most productive part of the entire UN meeting. Experts say a recent decision by the Obama administration provides an extremely positive signal going into the summit.

"The US discontinuation of its proposed missile shield program in Eastern Europe is a major kick-start for discussions about making the world nuclear-free," Gareis said.

In the past, many UN member states have complained that the body has focused too much on nuclear non-proliferation, particularly where Iran and North Korea are concerned, while ignoring the issue of disarmament among the world's major military powers, including the US, Russia and China.

Change on climate

Clearly, world leaders are anticipating change from Obama. And they got a preview of how extensive that change could be on Tuesday, when the US President addressed a special UN summit on the subject of climate protection.

"The security and stability of each nation and all peoples - our prosperity, our health, our safety - are in jeopardy," Obama said. "And the time we have to reverse this tide is running out."

Obama said he would discuss measures to phase out fossil fuel subsidies when he met with the heads of the world's leading economies later this week at the G20 summit in Pittsburgh. But he did not propose any major new US initiative on climate change.

Chinese President Hu Jintao told the climate summit that China would work more closely on developing renewable energy. He said the country was ready to slow down emissions by "a notable margin." But he failed to name specific figures.

Japanese Prime Minister Yukio Hatoyama pledged to give more aid to help developing countries deal with climate change and repeated his intention of reducing Japanese greenhouse gasses 25 percent from 1990 levels by 2020.

The climate summit comes ahead of a major UN climate conference to be held in Copenhagen, Denmark in December.

Author: Jefferson Chase

Editor: Rick Demarest