President Barack Obama is using his last day at the United Nations to push for peace in some of the world's most volatile regions.
He will focus on averting renewed conflict in Sudan and easing growing maritime tensions between China and its Southeast Asian neighbors on Friday. He will also press the military rulers of Burma to hold free and fair elections.
On Thursday, Obama spoke to the U.N. General Assembly about the Israeli - Palestinian conflict. In his address, he kept up the pressure on Israel and the Palestinians to reach a peace deal.
"If an agreement is not reached, Palestinians will never know the pride and dignity that comes with their own state," Obama said. "Israelis will never know the certainty and security that comes with sovereign and stable neighbors."
Obama also extended an olive branch to the Islamic Republic of Iran. The rogue state remains under heavy sanctions for its nuclear program, which is expected to soon produce a weapon.
"The door remains open to diplomacy should Iran choose to walk through it," Obama said.
Later that afternoon, Iranian President Mahmoud Ahmadinejad leveled charges that the U.S. was behind the Sept. 11, 2001 terrorist attacks on New York City and Washington, D.C.
"Some segments within the U.S. Government orchestrated the attack to reverse the declining American economy and its grips on the Middle East," Ahmadinejad told the assembled body of the world's nations.
The team representing the U.S. walked out in protest of the Iranian president's words. It was the second time in as many years that the U.S. delegation walked out while Ahmadinejad was giving a speech at the U.N.
The White House said Obama found the remarks deeply offensive. However, some said Ahmadinejad's words were not at all surprising.
"It's just an attempt by Ahmadinejad to change the focus from his problems in Iran to other issues that he's much more confident talking about," said Reza Aslan, author of the book, No Good But God.