In a televised speech to a vast crowd in the northwest province of Ardebil, Mahmoud Ahmadinejad, the Iranian president, rejected a UN security council resolution that demands Tehran halt sensitive nuclear work, and called for a Middle East free from the presence of the United States and Israel.
He said: "If they think they can use a resolution as a stick against us, they should know that Iranian people do not bend to language of force."
The UN security council adopted a resolution requiring Iran to suspend all activities related to uranium enrichment by August 31 or risk possible sanctions.
Ahmadinejad said he had spoken to Kofi Annan, the UN secretary-general, by telephone and "told him that we are willing to resolve the problem through negotiations... but by this resolution, we have lost our confidence in them".
He reiterated that Iran would respond on August 22 to the international package of incentives to suspend uranium enrichment that was offered by the five permanent members of the security council plus Germany.
"We will give our response on the announced date, and our reply will be based on defending the absolute rights of the Iranian people," he said, amid chants of "nuclear energy is our undeniable right".
Ahmadinejad said: "Today, we are fully mastering the nuclear fuel cycle for our peaceful atomic activities. It is a native technology... no one can take it away from us."
Ali Larijani, Iran's nuclear chief, also rejected the world's recourse to the security council.
He said: "If they think they can deprive Iran of its absolute right, they should know that even using the means of the security council will have no influence on Iran's determination."
Larijani also said that Iran intended to carry out "industrial enrichment", without elaborating, adding that this would not prevent the Islamic republic importing some of its nuclear fuel needs in the future.
Iran, OPEC's second largest oil exporter, insists it wants to enrich uranium only to make reactor fuel for power stations, but there is widespread suspicion that the country wants the capacity to make weapons-grade uranium.