Iran's president says his country may reconsider its membership in the nuclear Non-Proliferation Treaty if the West forces Tehran to limit its nuclear program. The Iranian leader's remarks, on the 27th anniversary of the Islamic Revolution, come as international pressure continues to mount over Iran's nuclear ambitions.

Mahmoud Ahmadinejad

Hundreds of thousands of Iranians gathered Saturday in Tehran's Freedom Square to commemorate the revolution that brought an Islamic theocracy to power.

Many marchers voiced their support for the Islamic regime's pursuit of nuclear energy, shouting "Nuclear energy is our inalienable right" and "Death to America."

In a harshly worded speech, President Mahmoud Ahmadinejad said Iran has conducted its nuclear activities peacefully, in accordance with international nuclear treaties, and in cooperation with the International Atomic Energy Agency. But he warned that if Iran's rights are threatened, it would reconsider its policies.

Iran has refused to heed international calls for it to abandon its nuclear program, insisting its ambitions are limited to the production of electricity, not bombs. Earlier this month, the IAEA board of governors voted to refer Iran to the United Nations Security Council, where it could face sanctions.

The Iranian leader also lashed out at arch-enemy Israel, saying the true holocaust was happening now in the Palestinian territories. Toward the end of last year, Mr. Ahmadinejad described the Nazi Holocaust of European Jewry as a "myth."

He has also said that Israel should be "wiped off the map."

In his speech Saturday, he also criticized the publication in Danish and other Western newspapers of a series of cartoons of the Prophet Muhammad. The drawings, which depict the prophet as a terrorist, have set off international demonstrations by angry Muslims and attacks on some Western embassies.

The Danish foreign ministry announced Saturday that it has temporarily withdrawn its ambassador and staff from its Tehran embassy, citing "serious and concrete threats" against the ambassador.