Kurdish forces seized two oil fields in northern Iraq and took over operations from a state-run oil company Friday, while Kurdish politicians formally suspended their participation in Prime Minister Nouri al-Maliki's government.

The moves escalated a feud between the Shiite-led central government and the autonomous Kurdish region driven by a Sunni insurgency that threatens to fragment Iraq along sectarian and ethnic lines three years after the withdrawal of U.S. troops.

The Kurdish forces took over production facilities at the Bai Hassan and Kirkuk oil fields near the city of Kirkuk, the Oil Ministry in Baghdad said. It called on the Kurds to withdraw immediately to avoid "dire consequences."