"Bullying must come to an end. Occupation must come to an end," he said in a wide-ranging interview on the sidelines of the U.N. General Assembly.
As for the rising violence in Syria, Obama told the U.N. delegates, "The future must not belong to a dictator who massacres his people. If there is a cause that cries out for protest in the world today, it is a regime that tortures children and shoots rockets at apartment buildings. We must remain engaged to assure that what began with citizens demanding their rights does not end in a cycle of sectarian violence."
In the AP interview, Ahmadinejad said Iran was one of nearly a dozen countries forming a new contact group to try to end the 18-month-old civil war in Syria. The group would include 10 or 11 countries in the Middle East and elsewhere and meet in New York "very soon," Ahmadinejad said.
Obama's defense of free speech was respectfully received by world leaders. Yet it was clear that different understandings abound on the proper exercise of free expression.
The foreign minister of Indonesia, home to the world's largest Muslim population, said Obama's speech was a "clarion call" for all nations to reject intolerance, calling it "an issue that galvanizes all of us." But Foreign Minister Marty Natalegawa added that freedom of expression should be exercised with consideration to morality and public order.
Dina Zakaria, a spokesman for the Muslim Brotherhood's political party Freedom and Justice, said cultural differences between the U.S. and the Muslim and Arab world over the limitations of freedom of expression will persist.
"No one can argue against freedom of expression, but the Western understanding of it is different from ours," she said. "Will this freedom allow for contempt of religion? For us it is different. For us it is a red line as Muslims and Christians as well."
Obama did not hesitate to underline some of the hopeful developments in the world under his watch.
"The war in Iraq is over, and our troops have come home," he said. "We have begun a transition in Afghanistan, and America and our allies will end our war on schedule in 2014. Al-Qaida has been weakened, and Osama bin Laden is no more. Nations have come together to lock down nuclear materials, and America and Russia are reducing our arsenals."
In one lighter moment in a somber speech, Obama drew laughter from the Assembly with one comment in his remarks on free speech: "I accept that people are going to call me awful things every day."
Benac reported from Washington. Associated Press writers Matthew Pennington at the United Nations and Sarah El Deeb in Cairo contributed to this report.
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