Vilified as a Holocaust denier, a supporter of terrorism and a backer of Iraqi insurgents, the president of Iran was actually able to make New Yorkers burst into laughter but not at a joke.

"In Iran we don't have homosexuals like in your country," Iranian President Mahmoud Ahmadinejad said at Columbia University on Monday in response to a question about the recent execution of two gay men there.

"In Iran we do not have this phenomenon," he continued. "I do not know who has told you we have it."

Loud laughs and boos broke from the audience of about 700 people, mostly students at the Ivy League school whose garb included "Stop Ahmadinejad's Evil" T-shirts.

Everyone from presidential candidates to September 11 families had expressed outrage that Ahmadinejad would speak there.

After his assertions that Israel persecutes Palestinians and that Iran's nuclear program is for energy not weapons, the Iranian leader's comment on gays broke the tension.

But it spurred strong reaction too.

"This is a sick joke," said Scott Long of Human Rights Watch, saying Iran tortures gays under a penal code that punishes homosexuality between men with the death penalty.

When Ahmadinejad, speaking in Farsi, actually tried to crack a joke, it drew no laughter, although maybe the nuance was lost in translation.

"Let me tell a joke here," Ahmadinejad said. "I think the politicians who are after atomic bombs, or testing them, making them, politically they are backward, retarded."

The crowd seemed uncertain how to react. Some applauded that pacifist sentiment, others seemed befuddled by the insensitive use of the word retarded.

DELUGE OF OBJECTIONS

Ahmadinejad's visit here was preceded by a deluge of objections when it became apparent he wanted to lay a wreath at Ground Zero and that he would speak at Columbia.

Presidential candidates from both major U.S political parties took swipes at the president of a country President George W. Bush calls part of "the axis of evil." They said he denied the Holocaust, supported terrorism and armed Iraqi insurgents.

U.S. Rep. Anthony Weiner of New York had a different way of capturing all that.

"Sometimes we have snakes slithering through the streets of New York," Weiner told protesters outside the United Nations, where Ahmadinejad will speak on Tuesday.

And in a city known for its blunt manners, the Iranian president's reception was bound to be frosty. The New York Daily News had the front page headline, "The Evil Has Landed."

At Columbia, university President Lee Bollinger pulled no punches. He called him a "petty and cruel dictator" and said his Holocaust denials suggested he was either "brazenly provocative or astonishingly uneducated."

"I feel the weight of the modern civilized world yearning to express the revulsion at what you stand for," Bollinger said to loud applause.

In retort, Ahmadinejad berated Bollinger as a rude host.

"Many parts of his speech were insults," he said. "We actually respect our students and the professors by allowing them to make their own judgments."

Not everybody objected to his speaking appearance.

"If the (Columbia) president thinks it's a good idea to have the leader from Iran come and talk to the students as an educational experience, I guess it's OK with me," Bush told Fox News.

(Additional reporting by Claudia Parsons, Michael Erman, Michelle Nichols and Megan Davies)

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