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President Mahmoud Ahmadinejad struck a defiant yet vague tone on Sunday, telling Iranians during the 28th anniversary of the Islamic Revolution that their country would not give up uranium enrichment but was prepared to negotiate.

The hard-line leader's remarks, which came days before a U.N. Security Council deadline demanding Tehran halt enrichment or face further sanctions, fell short of an expected announcement that Iran had started installing 3,000 centrifuges to enrich uranium at its Natanz plant.

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"The Iranian nation on Feb. 11, 2007, passed the arduous passes and stabilized its definite [nuclear] right," Ahmadinejad said. He did not elaborate, but his comments indicated that Iran had achieved proficiency in nuclear fuel cycle technology.

Ahmadinejad said his country's program would remain within the limits of the Nuclear Nonproliferation Treaty that bans production of nuclear weapons.

"We are prepared for dialogue but won't suspend our activities. ... The government will defend the rights of the Iranian nation within the framework of the law," he said.

While Iran insists it will not give up uranium enrichment, the United States and some of its allies fear the Islamic republic is more interested in enrichment's other application — creating the fissile core of nuclear warheads. Iran insists its program is peaceful and to generate electricity.

At a security conference in Germany, Iran's top nuclear negotiator said Sunday its nuclear program is not a threat to Israel or any other nation.

"We pose no threat and if we are conducting nuclear research and development we are no threat to Israel. We have no intention of aggression against any country," said the negotiator, Ali Larijani.

In Israel, Foreign Ministry spokesman Mark Regev dismissed Larijani's comments, saying Iran's government was trying without much success to convince the international community that its intentions are benign.

"There is a wall-to-wall consensus that the Iranian nuclear program is indeed military and aggressive and a threat to world peace," he said.

Ahmadinejad, who has said Israel should be "wiped off the map," promised that Iran's nuclear technology advances will gradually be made public over the course of the next two months until April 9. He did not explain what would happen on that date, but it marks the one year anniversary of Iran's announcement that it had enriched uranium for the first time.

The Iranian leader suggested last week that Tehran would announce that it had begun installing a new assembly of 3,000 centrifuges in an underground portion of its uranium enrichment facility at Natanz — in what would be a major jump in its nuclear program.

It is widely believed, however, that moderates among the ruling Islamic establishment advised him against such a provocative statement.

"After the U.N. Security Council imposed sanctions on Iran last December, Ahmadinejad has come under pressure at home and abroad to moderate his tone. He refused to make that announcement not to further provoke the West at this crucial time," political analyst Iraj Jamshidi said.

The Security Council first imposed limited sanctions in December over Iran's refusal to halt enrichment and has threatened to further sanctions later this month if it continues to refuse to roll back its program.

Ahmadinejad's comments Sunday were part of a speech that was broadcast live during nationwide rallies marking the 28th anniversary of the Islamic Revolution. Hundreds of thousands of Iranians gathered at a Tehran square, chanting slogans including: "Death to America!"

On Feb. 11, 1979, Iran's imperial armed forces withdrew support for the U.S.-backed monarchy and declared its allegiance to Ayatollah Ruhollah Khomeini after a popular peaceful uprising throughout Iran. Khomeini's followers seized control of the capital and two months later declared Iran an Islamic republic.

Sunday's rallies also were a referendum on the country's nuclear program. Ahmadinejad's government, whose nuclear diplomacy has been criticized domestically by both reformers and conservatives in recent weeks, wanted to show that the nation stands united behind him despite mounting pressures from the West.

Speaking in Munich, Germany, Larijani also said his country was prepared to settle all outstanding issues with the U.N. nuclear watchdog, the International Atomic Energy Agency, within three weeks.

The IAEA has said it has found no evidence that Iran is trying to build nuclear weapons, but the watchdog has suspended some aid to Iran and criticized the country for concealing certain nuclear activities and failing to answer questions about its program.

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