Disputes about Tehran's nuclear aims spilled over on Monday into a 139-nation meeting of the International Atomic Energy Agency, with Iranian vice-president deriding the 'absurdity' of a threat to refer his country to the UN Security Council.

United States and European representatives defended a decision taken last week by the IAEA's governing board to carry out such a move as early as November, and IAEA head Mohamed ElBaradei urged Tehran to cooperate with his agency to defuse suspicions about its nuclear agenda.

Much of the five-day meeting focuses on routine matters. But the dispute over Iran had been expected to cast its shadow over the gathering.

"The resolution...demonstrates how issues can reach the borders of absurdity, when politics overwhelms the work of the agency," Iranian Vice President Reza Aghazadeh told the meeting, saying the Security Council motion had no legal base.

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"Why such a forceful push to resort to the security council," asked Aghazadeh, who is also head of his country's nuclear programme. "What magical means can the council offer for a settlement, except to...provoke an unwanted crisis?"

But speaking for Britain and the European Union, British delegate Robert Wright said the resolution on possible future Security Council referral reflected the fact that 'over the past two years, Iran has failed to honour its commitments'.

Gregory Schulte, the chief US representative to the IAEA said Iran served as an example of the 'pernicious and defiant misuse of nuclear tehnology', threatening to irreversibly damage nonproliferation efforts. 'The onus is on Iran to come into compliance with its international obligations' to dispel fears about its nuclear intentions, he said.

Elbaradei hailed North Korea's recent announcement that it is willing to give up nuclear arms development but challenged Iran to reduce the kind of suspicions about its nuclear agena that led to the IAEA board resolution.

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Among key areas of concern, ElBaradei named North Korea's nuclear weapons threat, suspicions that Iran may be looking to develop a nuclear weapons programme and revelations over the past two years of nuclear black market networks.

Those developments and revelations pose 'an unprecedented array of challenges to the nonprolifeation and arms control regime', he told the assembly.

Earlier on Monday, the conference approved the reappointment of El Baradei for a third term as head of the UN nuclear watchdog agency, reflecting formal backing of his leadership after the US ended its opposition to his tenure.

The move, by acclamation, had been expected after the IAEA's board agreed to the reappointment earlier this year.  Much of previous US opposition to El Baradei was because Washington viewed the Egyptian diplomat as being too soft on Iran for not declaring it in violation of the Nuclear Nonproliferation Treaty.

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