SYDNEY, Sept 28 Rio Tinto Ltd/Plc RIO.AXRIO.L said on Friday its sharehol

SYDNEY, Sept 28 (Reuters) Rio Tinto Ltd/Plc said on Friday its shareholders overwhelmingly approved its proposal to acquire Canadian aluminium group Alcan Ltd for $38.1 billion.

Shareholders voted 708.6 million in favour to 19.6 million against at extraordinary general meetings, held in Melbourne on Friday and in London on Sept. 14.

Rio was aiming to complete the acquisition in the fourth quarter of 2007 and was working with various regulatory agencies over approvals, Rio Chairman Paul Skinner said in Melbourne.

Rio on Sept. 17 extended the offer to Oct. 23 to allow time to gain regulatory approvals. The all-cash offer of $101 a share pitched in July had been due to close on Sept. 24.

Rio Tinto already has approvals from U.S. and Canadian competition regulators, but still needs clearances from the European Union and Australia, which are expected on Oct. 2 and Oct. 10 respectively, the company has said.

The acquisition would make Rio the world's largest aluminium producer ahead of Russia's UC RUSAL.

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