Iran''s envoy to the UN told its General Assembly on Tuesday that his country would not give in to UN Security Council demands to suspend uranium enrichment.

The Islamic Republic is currently under three sets of relatively mild UN Security Council sanctions for defying demands to halt uranium enrichment, which Tehran says is aimed purely at electricity production, and has pledged to continue uranium enrichment regardless of international sanctions.

"All reports by the IAEA since November 2003 have contained evidence of the peaceful nature of Iran''s nuclear program," Mohammad Khazaee said. "The demand to suspend enrichment is illegal, beyond and in breach of the Nuclear Non-Proliferation Treaty. Iran will never accept these illegal demands."

The head of the International Atomic Energy Agency (IAEA) called on the Islamic Republic to facilitate an inspection of the country''s nuclear program.

"I am calling on Iran to take all measures of transparency needed to build confidence in the exclusively peaceful nature of its nuclear program as soon as possible," Mohammad ElBaradei told the General Assembly.

The IAEA, which is the UN''s nuclear watchdog, wants Iran to clarify suspected links between uranium enrichment and tests of high explosives and missile technology allegedly being developed by Iranian scientists by granting access to sites, documents and the relevant officials.

The official said his agency could continue inspecting materials earlier declared by Iran for their possible military applications. But he added that there were still many questions on Tehran''s nuclear program.

"I regret that we have not been able to make it completely clear as to the lack of undeclared nuclear materials and activity in Iran," ElBaradei said.

Russia''s UN envoy said Moscow was ready to assist countries interested in civilian nuclear energy, including in peaceful uranium enrichment. Vitaly Churkin said the international uranium enrichment center due to be opened in the East Siberian town of Angarsk in collaboration with Kazakhstan "is open to third countries without any political preconditions."

Russia earlier proposed that Iran join the project, which could go some way to ensuring the transparency of Tehran''s nuclear program. The Iranian authorities yet to agree to the Russian offer, however.