UPDATE 1-Iraq election set for Jan. 21 after new law passed

* Date to be confirmed by presidential council

* Parliament to have more seats to reflect bigger population

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By Muhanad Mohammed

BAGHDAD, Nov 9 (Reuters) - Iraqis will vote in a general election on Jan. 21 now that parliament has passed a law needed for a vote to take place, the head of the country's electoral commission said on Monday.

The ballot was originally set for Jan. 16, but electoral authorities said the delay in passing the law had made it impossible to organise by then. Parliament ended weeks of disagreement about the fate of the disputed city of Kirkuk and passed the electoral law on Sunday. [ID:nL8179469]

Faraj al-Haidari, head of the electoral commission, told Reuters that the new date of Jan. 21 needed to be approved by a presidency council of President Jalal Talabani and two vice-presidents.

"I don't think that date will change," he said.

Prolonged arguing over the law had cast doubt on the U.S. military's plans to end combat operations in Iraq by Aug. 31, 2010, ahead of a full withdrawal by the end of 2011.