Russia today offered its most outspoken support yet of the controversial nuclear programme in Iran, its neighbour and trading partner.

"Our advice to our Iranian colleagues and friends is to complete work with the International Atomic Energy Authority and to calmly continue its nuclear energy programme... and on this path we are ready to provide assistance to Iran," Sergei Kislyak, the Deputy Foreign Minister, told a security conference in Moscow.

"The search for a solution must follow the route of diplomacy, and our position is that the instrument for resolving this problem, as before, must remain the IAEA, as we don’t have another international agency that has such authority and competence in the non-proliferation area."

Earlier, Iran's envoy to the UN's nuclear watchdog promised that Iran was ready for "full" co-operation with the IAEA over its controversial uranium enrichment programme.

Ali Asghar Soltanieh told the same security conference in Moscow that Tehran was prepared to answer all questions about its nuclear programme, RIA Novosti news agency reported.

"Iran plans to continue its full co-operation with the IAEA. We are ready to eliminate all outstanding doubts about our nuclear dossier," Mr Soltanieh, was quoted as saying in a speech.

The US and Europe have been pushing at the UN Security Council for sanctions against Iran, because of its refusal to suspend its enrichment programme.

Last week President Mahmoud Ahmadinejad announced that Iranian scientists had succeeeded for the first time in enriching uranium by 3.5 per cent, qualifying his country for membership of the "nuclear club". Mr Ahmadinejad's claims have yet to be independently verified.

Iran says that it is seeking nuclear power purely for peaceful energy generation, but Washington believes that it is concealing a desire to develop an atomic bomb. But Russia said there was no proof Iran was seeking nuclear weapons.

"One can speak of sanctions only after the appearance of concrete facts proving that Iran is not engaged exclusively in peaceful nuclear activities," Mikhail Kamynin, a Foreign Ministry spokesman, told the ITAR-Tass news agency.

Nikolai Spassky, deputy head of the Kremlin Security Council, put it even more bluntly. "There is no such issue (of sanctions) for us," he was quoted as saying by the RIA-Novosti news agency. "We are not discussing it."

Mr Soltanieh said that he was confident that the IAEA "will resolve this problem with a technical - and not political - point of view through negotiation and discussion in the framework of this international organisation."

The Security Council is waiting to see if Iran adheres to an April 28 deadline for it to halt uranium enrichment and to cooperate fully with inspectors from the Vienna-based IAEA.

America and Britain have said that if Iran does not comply with the April 28 deadline to stop enrichment, they will seek a resolution that would make the demand compulsory.

But Russia and China, both trading partners of Iran, have said that they will use their vetoes as permanent members of the Security Council to block any punitive action against Iran.

Yesterday, Moscow rejected a US call to end co-operation in constructing the US$800 million ($648 million) Bushehr nuclear power plant in southern Iran.

Also yesterday, a senior UN nuclear inspector put off a trip to Iran in what diplomats in Vienna said was a clear sign that Tehran is failing to give the UN atomic agency key concessions it demands.

But Mr Soltanieh reportedly disputed that today, claiming that the Iranian leadership was prepared to place its nuclear facilities under the control of the IAEA, although Russian news agencies provided no direct quotation from him to this effect.

The Iranian envoy said that Tehran had been conducting nuclear energy research for more than 30 years.

"It is our right to continue research under IAEA control," Mr Soltanieh said. "The United States and Europe have no right to demand from us an immediate halt to our research, which is strictly for peaceful ends."

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