Iran's top nuclear official has vowed that the clerical regime would press on with uranium enrichment work despite mounting international pressure to freeze its sensitive nuclear activities. "Why should Iran suspend its research activities?" Ali Larijani, the head of the Supreme National Security Council, was quoted as saying by the official IRNA news agency. Enrichment can be extended from making reactor fuel to the production of warheads, but Larijani branded a UN Security Council demand for a suspension by April 28 as "not rational". "One should not follow such propositions... which are not rational," he said, adding: "Iran will follow its nuclear programme with patience." Last Tuesday, Iran announced it had successfully enriched uranium to the level needed for reactor fuel, reigniting fears that the hardline regime would soon acquire the technical know-how to make bombs. The deputy head of Iran's Atomic Energy Organisation, Mohammad Saidi, argued that the UN nuclear watchdog had failed to find any proof that Iran's programme was anything other than a legitimate effort to generate electricity. "Therefore, there is no need to continue a suspension," he told the Etemad-Melli newspaper. "These countries have to accept the reality and realise they are talking with a country that masters this tech