Ahmadinejad, who is due to arrive in New York for the United Nations General Assembly, said Tehran's nuclear ambitions were open and being conducted in accordance with the UN's International Atomic Energy Agency.

"You have to appreciate we don't need a nuclear bomb. We don't need that. What need do we have for a bomb?" the Iranian leader said in an interview with CBS television to be broadcast later on Sunday.

He added that there was no reason to think that the United States and Washington were on a collision course to war over Tehran's nuclear ambitions, which have been roundly condemned by the international community.

"It's wrong to think that Iran and the US are walking towards war. Who says so? Why should we go to war? There is no war in the offing," the he said in the interview, according to a transcript released by CBS television.

"Our plan and programme is very transparent. We are under the supervision of the agency. Everything is on the table. We have nothing to hide," he said, adding: "Our activities are very peaceful."

"The time of the bomb is passed," he added.

Iran's nuclear ambitions have been under international scrutiny and put Tehran under a raft of United Nations-backed sanctions, especially due to the Islamic regime's attitude towards Israel.