President Mahmoud Ahmadinejad of Iran ran through his standard talking points at his annual gathering with American journalists on Tuesday, denying that dissidents languished in jail or that economic sanctions were biting, and rejecting the idea that Tehran deserved anything less than a gold star for its nuclear inspection record. But this time, he embroidered his remarks with a little fresh bluster.

Seated at a conference table surrounded by news editors and television producers, the Iranian president told his breakfast guests that, should the United States attack Iran over its nuclear program, it would become embroiled in a war that would make previous American conflicts pale in comparison.

“The United States has never entered a real war, not in Vietnam, nor in Afghanistan, nor even World War II,” Mr. Ahmadinejad said during the meeting at a hotel in Midtown Manhattan, part of what has become his ritual charm offensive when he attends the United Nations General Assembly. “War is not just bombing someplace. When it starts, it has no limits.”

At the same time, he rejected the idea that tensions would ever reach that point, dismissing the threat of an attack on Iran as mere psychological warfare. “We have always been prepared to talk,” Mr. Ahmadinejad said.