WASHINGTON, D.C. — The Director of the US Defense Intelligence Agency (DIA) told senators during a hearing that the question of independence for the Kurdistan Region is to be expected, adding that resolving disagreements over the Kirkuk oil will be significant political challenges for the Iraqi government.

"Kurdish independence is on a trajectory where it is probably not if but when. And it will complicate the situation unless there's an agreement in Baghdad," Lt. Gen. Vincent Stewart, whose role is to provide intelligence assessments, said on Tuesday.

Stewart told the Senate's Armed Forces Committee that the ability of the Erbil and Baghdad to reach an understanding is essential to avoid renewed conflicts in the region.

"So this is a significant referendum that comes up in October this year," Stewart stated.

Authorities with the Kurdistan Regional Government (KRG) have announced their plan to hold a referendum this year.

"On 30 March, during my visit to Erbil, President [Masoud] Barzani stated the intention to hold a referendum on the status of the region in 2017. He added that while the aim was not to immediately declare independence, the result would show the world the will of the people," stated a quarterly Secretary-General report from Antonio Guterres to the UN Security Council.

The Kurdish Peshmerga forces supported by the US-led international coalition have played a major role in the war against ISIS in Iraq, securing the borders of the Kurdistan Region against the militant group.

In 2014, the Peshmerga also prevented the group from taking control of the oil rich region of Kirkuk when the Iraqi army fled conflicts from the incoming militants.

Although the Kurds have a historical claim over Kirkuk, Stewart said "Resolving the Kirkuk oil field and the revenues associated with the oil fields, resolving the ownership of the city of Kirkuk, will be significant political challenges for the Iraqi government."

Erbil has said the referendum is to cover nearly all disputed territories outside the administration of the Kurdistan Regional Government (KRG) in places such as Kirkuk, Shingal, Khanaqin and areas in Nineveh Plains which were liberated from ISIS militants over the past two years. 

“With regard to the disputed areas...those places from our perspective are Kurdistani places,” Rozh Nuri Shawes, a senior official from the ruling Kurdistan Democratic Party (KDP) told reporters after an April 2 meeting between Kurdish officials and foreign missions in Erbil. 

Hoshyar Zebari, who is a senior member of the ruling Kurdistan Democratic Party (KDP), and longest serving Iraqi FM since the fall of the former Iraqi regime 14 years ago, later clarified to Rudaw that should the councils from the cities and provinces that come under the disputed areas call on the Kurdistan Region to hold the independence referendum, the Kurdish government will act on their request, and conduct the referendum.

The issue of the disputed areas, otherwise called Kurdistani areas outside the Kurdistan Region, was put into the Iraqi constitution after the removal of the Baath party in Iraq. It concerns areas claimed by both Erbil and Baghdad, such as Kirkuk and some areas in Nineveh. 

Kurdish and Iraqi officials have been engaged in a continued dialogue to resolve outstanding disagreements.