The United States warned that an independence referendum Monday for the Kurdish Regional Government( KRG) to break away from Baghdad will "increase instability," State Department spokeswoman Heather Nauert said in a statement.

She noted that the United States is deeply disappointed that the Kurdistan Regional Government decided to conduct a unilateral referendum on independence, including in areas outside of the Iraqi Kurdistan Region. The United States' historic relationship with the people of the Iraqi Kurdistan Region will not change in light of today's non-binding referendum, but we believe this step will increase instability and hardships for the Kurdistan region and its people."

Heather Nauert said that "the unilateral referendum will greatly complicate the Kurdistan Regional Government's relationship with both the Government of Iraq and neighboring states. The fight against ISIS is not over, and extremist groups are seeking to exploit instability and discord. We believe all sides should engage constructively in a dialogue to improve the future of all Iraqis. The United States opposes violence and unilateral moves by any party to alter boundaries.

According to her, the United States supports a united, federal, democratic and prosperous Iraq and will continue to seek opportunities to assist Iraqis to fulfill their aspirations within the framework of the constitution.