TEHRAN, Iran - Iran's hard-line President Mahmoud Ahmadinejad on Tuesday challenged President Bush to a televised debate, a proposal the White House immediately dismissed as a "diversion."

Iranian President Mahmoud Ahmadinejad addresses a press conference in Tehran. Ahmadinejad challenged his US counterpart George W. Bush to a live television debate as he shrugged off the threat of sanctions two days ahead of a UN deadline for Iran to halt sensitive atomic work.[AFP]

The challenge came during a freewheeling, 2 1/2-hour news conference and only two days before a U.N. Security Council ultimatum demanding Iran roll back its suspect nuclear program.

Ahmadinejad said no one can prevent Iran from pursuing what he called a peaceful nuclear program, not even U.N. Secretary-General Kofi Annan, who was expected to visit here Saturday.

"Mr. Annan, too, has to move within the framework of international regulations. No one has a special right or advantage," he said.

The U.N. Security Council has set Thursday as a deadline for Iran to suspend uranium enrichment, a process that can produce either fuel for a reactor or material for weapons. Iran has refused any immediate suspension, calling the deadline illegal, and instead this week offered a counterproposal that the United States and some European nations said fell short.

Ahmadinejad's latest show of defiance seemed to solidify the country's determination to snub the Security Council, following a string of war games and uncompromising public statements this month on the nuclear standoff. But whether the U.S. can muster enough support on the 15-nation council to impose economic or political sanctions remains in question.

In his criticism of the Security Council, Ahmadinejad singled out two of its permanent members with veto power - the United States and Britain for what he called their failure to listen to the needs of other countries.

"The U.S. and Britain are the source of many tensions," he said. "At the Security Council, where they have to protect security, they enjoy the veto right. If anybody confronts them, there is no place to take complaints to."

"This (veto right) is the source of problems of the world," he said. "It is an insult to the dignity, independence, freedom and sovereignty of nations."

The United States' ambassador to the U.N., John Bolton, dismissed Ahmadinejad's remarks, and Britain's ambassador to the world body suggested, somewhat tongue-in-cheek, that the comments were mild compared to Ahmadinejad's past sharp rhetoric against Israel and others.

"Given some of the comments he makes, we should probably take that as a compliment," Ambassador Emyr Jones-Parry said.

After an opening statement, Ahmadinejad allowed Iranian reporters to ask questions. One Iranian journalist stood up and showered him with praise. The local reporters were more casually dressed than the foreign press, who later were allowed to question him about a range of topics. At one point, the president joked that he would call on a particular reporter because he and Ahmadinejad were wearing similar outfits.

In his challenge to Bush, Ahmadinejad said the debate should focus on "world issues and the ways of solving the problems of the international community."

He did not rule out the possibility of direct diplomatic talks with the United States, saying it could happen if unspecified conditions were met. But he criticized the United States for "living in the dream of getting the Iranian nation back to 30 years ago," before the Islamic revolution.

Earlier this year, Ahmadinejad wrote a letter to Bush portraying the world as filled with an "ever-increasing global hatred of the American government." Washington promptly dismissed the letter as irrelevant and not addressing the key issue of Iran's disputed nuclear program.

The Bush administration had a similar reaction Tuesday to the debate idea. White House spokeswoman Dana Perino said it was "just a diversion from the legitimate concerns that the international community, not just the U.S., has about Iran's behavior, from support for terrorism to pursuit of a nuclear weapons capability."

Iran offered last week to pursue negotiations on its nuclear program but declined to suspend uranium enrichment as a precondition to talks. The U.S. State Department described the Iranian proposal as serious but said it fell short of what Iran must do.

The Bush administration this week reaffirmed its intent to pursue U.N. sanctions against Iran if it defies the approaching deadline. But Russia, whose support for sanctions is essential, has publicly counseled patience with Iran, a possible signal of reluctance to go along with the U.S.

Divisions within the international community over Iran's nuclear program could hand a victory to Tehran, French Foreign Minister Philippe Douste-Blazy warned in an interview released Tuesday.

"The international community must not become divided, to cut itself in two. That would be a victory for the Iranians," Douste-Blazy told Euronews television.

Jones-Parry, the British ambassador, said the Security Council will need until mid-September before acting on its threat to punish Iran if Tehran's leaders flout the Thursday deadline. He said the council would first need to receive a report from the U.N. nuclear watchdog, the International Atomic Energy Agency, on Iran's compliance with the resolution.

Tehran has pursued a confrontational stance on the nuclear issue since Ahmadinejad's election last year. He has often used the issue to encourage a sense of national pride among Iranians by standing up to the United States and other Western countries.

He and other Iranian officials repeatedly have said the country's nuclear program is intended solely to generate electricity, while the United States and Europe contend Iran secretly aims to develop weapons.

Washington recently warned against a heavy-water plant that Iran opened over the weekend, fearing it could be used as a second track toward building a warhead.

Heavy water contains a heavier hydrogen particle that allows a nuclear reactor to run on the natural uranium mined by Iran, without undergoing the enrichment process. But the spent fuel from a heavy-water reactor can be reprocessed to extract plutonium for use in a bomb.

Large-scale military exercises also have been under way in Iran over the past month. Iran says the weaponry is intended to defend itself against the possibility of a U.S. attack and has expressed worry about Israeli threats to destroy its nuclear facilities.

Despite intense disagreement over suspected nuclear weapons programs and terrorism, the Bush administration decided Tuesday to allow former Iranian President Mohammad Khatami to visit the United States.

Khatami plans to attend a U.N. conference Sept. 5-6 in New York to promote dialogue, then speak at the Washington National Cathedral on Sept. 7 on the role of Islam, Christianity and Judaism in shaping peace.

He would be the most senior Iranian official to visit Washington since Islamic fundamentalists seized the U.S. Embassy in Tehran in 1979 and held Americans there hostage for 444 days.