In a round of intense diplomacy in the wake of violent anti-US protests, US Secretary of State Hillary Clinton met a series of Muslim leaders and urged people to work together against extremists.
"All of us need to stand together to resist these forces and to support the democratic transitions under way in North Africa and the Middle East," Clinton told a donors forum.
"Unity on this throughout the international community is crucial because extremists around the world are working hard to drive us apart."
She was addressing a meeting of the Clinton Global Initiative, founded by her husband, former president Bill Clinton, at which she praised the Libyan people in Benghazi for rising up last week against armed militias.
Residents drove out the militants blamed for a September 11 attack on the US mission in which ambassador Chris Stevens and three other Americans were killed, at the start of a wave of protests in which around 50 people have died.
"The people of the Arab world did not set out to trade the tyranny of a dictator for the tyranny of a mob. There is no dignity in that," Clinton said, before she met with the leaders of Libya, Pakistan, Afghanistan and Egypt.
"The people of Benghazi sent this message loudly and clearly on Friday when they forcefully rejected the extremists in their midst and reclaimed the honor and dignity of a courageous city.
Libya's new authorities have now launched a crackdown after the massive anti-militia protests in Benghazi when hundreds of people stormed the bases of militias, sparking clashes that left 11 dead and dozens wounded.
And on Monday, at their first face-to-face talks, new Libyan leader Mohamed al-Megaryef vowed to Clinton that his country would not be a burden to the international community.
Clinton has launched an official review into the events in Benghazi, including whether security measures were properly implemented, amid allegations the State Department failed to adequately protect its diplomatic staff there.
Libya would shoulder the "grave responsibility, for this tragedy and also let us look at the necessity to expedite the investigation in the incident and to bring to justice the perpetrators," Megaryef added.
The events in Benghazi did "not express in any way the conscience of the Libyan people, their aspirations, their hopes or their sentiments towards the American people," he said at the start of their talks in a New York hotel.
The attack "was a very painful, huge tragedy, not only for the American people and the families of the victims, but also for the Libyan people," he added, speaking softly, mostly through a translator.
Clinton thanked Megaryef for his government's efforts and vowed the United States would stand by Libya as it forges a fledgling democracy.
US President Barack Obama and Clinton have denounced the film "Innocence of Muslims" which triggered the wave of unrest, but have stressed repeatedly that there is no justification for violence.
Clinton also met Monday with Pakistani President Asif Ali Zardari and thanked him for Pakistan's handling of several days of violent anti-US protests which swept the country last week.
"One or two insane persons should not be allowed to endanger world peace in the garb of freedom of expression," Zardari said at the meeting, according to a statement from the Pakistani embassy.
A senior State Department official said afterwards ties between the two uneasy allies "are moving upwards, in a positive direction."
"We've been working in a very diligent, disciplined, workman-like manner over the course of these last 18 months which have been very difficult, and especially over the last several months... to get this back on track."
Clinton also met with Afghan President Hamid Karzai for almost an hour and discussed moves to launch talks on a new bilateral security agreement as US and international troops prepare to leave Afghanistan by the end of 2014.
Later Monday, Clinton was meeting with Egypt's new Islamist President Mohamed Morsi. The two last met when Clinton visited Egypt in July and pressed the country's new leaders to respect the rights of all Egyptians.