"If they (Ahmadinejad and Bush) are to debate, the UN is the best place for the purpose," the official IRNA news agency quoted Gholam-Hossein Elham as saying.

Asked whether Ahmadinejad is ready to hold talks with Bush, Elham underlined that "the matter is to hold debate but not talks or dialogue."

The Iranian president is to arrive in New York on Tuesday to attend the UN General Assembly meeting, IRNA said.

Bush, who also heads to the United Nations for a three-day trip, last week ruled out any talks with Ahmadinejad before Iran suspends its uranium enrichment.

Ahmadinejad in late August proposed to have a live television debate with his U.S. counterpart on "world issues" but was dismissed by the White House who saw the proposal as a diversion from Iran's nuclear issue.

The United States has accused Iran of trying to develop nuclear weapons under the cover of civilian nuclear programs while Iran insists that its nuclear programs are for peaceful purposes only.

The United States is now seeking to impose sanctions on Iran for its refusal to comply with a UN Security Council resolution demanding Iran suspend by Aug. 31 all enrichment-related and reprocessing activities.

At an informal meeting in Brussels earlier this month, European Union foreign ministers decided to maintain serious talks with Tehran in efforts to solve Iran's nuclear issue through diplomacy.