The region, which had enjoyed unprecedented autonomy for years, has been in turmoil since the independence referendum a month ago prompted military and economic retaliation from Iraq’s central government in Baghdad.
The loss of control of Kirkuk oil fields is likely to starve the KRG of vital oil revenue and cause deep concern to global trading houses.
The Kurds held a referendum on independence on September 25 that Baghdad called illegal.
A path toward reconciliation will be a long, arduous test of nerves that could expose the US-backed war effort in Iraq to risks from insurgents and militants.
Turkey has been battling a three-decade insurgency in its largely Kurdish southeast and fears the referendum will inflame separatist tensions at home.
Iraq considers the vote unconstitutional, especially as it was held not only within official KRG territory itself but also on disputed territory held by Kurds elsewhere in northern Iraq.
The Kurds consider Monday’s referendum to be a historic step in the generations-old quest for a state of their own.