Columbia University has defended as a matter of free speech its decision to allow Ahmadinejad to speak today.
Some politicians and Jewish groups have criticized the visit to Columbia by the Iranian leader, who has questioned evidence of the Holocaust and called for Israel to be "wiped off the map."
Ahead of his arrival in New York, Ahmadinejad told the U.S. television network CBS that he did not believe Iran and the United States were heading toward war. Referring to western accusations Iran is secretly trying to develop nuclear weapons, he also said Iran had no use for a nuclear bomb.
Ahmadinejad is due to address the UN General Assembly in New York on September 25.