Iranian President Mahmoud Ahmadinejad told the U.N. General Assembly Tuesday that a few "bullying" world powers are trying to thwart what he says is his country's peaceful nuclear program. He spoke only a few hours after President Bush told the forum Iran's nuclear ambitions are a threat to world civilization. VOA's David Gollust reports from our U.N. bureau.

The Iranian leader sounded a defiant tone at the United Nations, where preliminary consultations have been held on a possible fourth sanctions resolutions against Tehran in the Security Council because of its refusal to halt uranium enrichment.

Mr. Ahmadinejad, in a policy address heavy with religious references, said Iran like other countries has an "inalienable" right to peaceful nuclear energy but said a few bullying world powers have tried to thwart Iran's program through political and economic pressure.

The International Atomic Energy Agency recently released a report detailing Iranian non-cooperation with its effort to determine if Tehran has a secret nuclear weapons program. But the Iranian President, said his government has fully cooperated with IAEA inspectors, who he said should redirect their scrutiny to the world's declared nuclear powers:

"The Iranian nation is for dialogue. But it has not accepted and will not accept illegal demands. The time has come for the IAEA to present a clear report to the international community on its monitoring of the disarmament of the nuclear powers and their nuclear activities, and for a disarmament committee to be established by independent states to monitor the disarmament of these nuclear powers," he said.

No senior U.S. diplomats were present in the General Assembly hall for Mr. Ahmadinejad's speech though the Iranian president and other officials attended President Bush's speech earlier in the day.

In it, Mr. Bush said Iran is among the few remaining countries that sponsor terrorism and said its nuclear program, along with that of North Korea, demands world attention. "We must remain vigilant against proliferation - by fully implementing the terms of Security Council resolution 1540 and enforcing sanctions against North Korea and Iran. We must not relent until our people are safe from this threat to civilization," he said.

Iran has refused to accept a big-power offer of economic and diplomatic incentives to halt a uranium enrichment program believed by the United States and European allies to be weapons related.

Secretary of State Condoleezza Rice had been expected to meet foreign minister colleagues from the five permanent U.N. Security Council member countries and Germany in New York on Thursday to discuss a possible new sanctions resolution against Tehran.

However, a State Department spokesman said late Tuesday the meeting would not be held. He did not elaborate but the Russian foreign ministry said in Moscow it saw no urgent need to schedule such a meeting amid the heavy volume of other business of the new General Assembly session.

U.S.-Russian relations have been tense in recent weeks amid sharp American criticism of Moscow's intervention in Georgia.

Bush administration officials have said there is a big power consensus for a new sanctions resolution despite the Georgia disagreement, though Russian President Dmitry Medvedev said last week new sanctions were "untimely."

Mr. Ahmadinejad's U.N. address, his fourth since taking office in 2005, again included scathing references to Israel, which he referred to as the Zionist regime, and which he said is on what he termed "a definite slope to collapse."

In a new theme, the Iranian President also asserted, what he termed, "the American empire is reaching the end of its road." He said in earlier interviews with U.S. media outlets that the current Wall Street financial crisis stems from the economic burden of years of heavy U.S. military involvement around the world.