UNITED NATIONS (CNN) -- U.N. Secretary-General Ban Ki-moon Wednesday urged global leaders to unite and work together to face many of the world's challenges.
"Amid many crises ... food, energy, recession and pandemic flu, hitting all at once ... the world looks to us for answers. If ever there were a time to act in a spirit of renewed multilateralism ... a moment to create a United Nations of genuine collective action ... it is now," he said.
"Now is our time. A time to put the 'united' back into the United Nations. United in purpose. United in action."
In the opening speech of the U.N. General Assembly's annual debate, Ban focused on the importance of tackling "the threat of catastrophic climate change" and expressed hope that nations working to deal with the problem will succeed.
He touched on nuclear disarmament, saying "let us make this the year we agreed to banish the bomb."
"For too long, this great cause has lain dormant. That is why, last October, I proposed a 5-point plan for putting disarmament back on the global agenda. And now ... the international climate is changing."
He cited pledges from Russia and the United States to cut their nuclear arsenals
Ban also talked of the need to fight world poverty, what he said was an urgent development with "near-poor" people becoming "the new poor." He cited the possibility that 100 million people "could fall below the poverty line this year."
Noting the economic crisis across the world, the secretary-general said markets may be bouncing back, but incomes and jobs are not.
"People are angry. They believe the global economy is stacked against them," he said, mentioning U.N. initiatives to address such economic problems.
Other urgent problems he noted include sexual violence, child mortality, and empowering women.
He underscored the importance of the International Criminal Court and named trouble spots across the globe that continue to require urgent attention.
One of those is the grinding civil warfare in Sudan's Darfur region and other parts of that country, where there has been some progress but persistent challenges.
Nearby, Somalia "continues to demand attention, whether to support African peacekeepers and the government or international anti-piracy efforts," he said.
He talked about the importance of resettlement and reconciliation in Sri Lanka, which had been wracked by civil war. He focused on the need "for freedom and democracy in Myanmar and releasing political prisoners there.
"If next year's elections are to be accepted as credible and inclusive, all political prisoners must be released, including Daw Aung San Suu Kyi," the country's opposition leader who has long been under house arrest.
Ban made reference to the conflict in Israel and the Palestinian territories, and called for efforts "to stop the bloodshed in Gaza.
"Yet people continue to suffer. Issues of justice and accountability need to be addressed. We must revive negotiations toward a two-state solution and a comprehensive peace in the Middle East."
Ban said there has been progress in Afghanistan, even though "recent elections revealed serious defects. Yet we should not forget the progress made ... progress we can build on."
The secretary-general also cited "significant progress" in unstable environments such as "Timor Leste, Haiti, Sierra Leone and Nepal. We see quiet progress in Iraq ... and fresh opportunities in Cyprus."
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