Iraq's parliament passed a long-delayed election law on Sunday, making the way for a national election in January.

Lawmakers overcame disagreements over the disputed city of Kirkuk to pass the measure, a lawmaker told Reuters.

The key hurdle to the law's passage had been how to apportion votes in the oil-rich city — a city claimed by both Arabs and Kurds — in the world's 11th largest oil producing nation.

The issue has been especially worrying because if the election law had not passed soon, it would have delayed the Jan. 16 election and U.S. plans to withdraw their forces.

The Associated Press contributed to this report.