People in Iraq's autonomous region of Kurdistan are voting in an independence referendum, amid rising tensions and international opposition.
Polls opened at 05:00 GMT with balloting also taking place in the disputed areas between the northern city of Erbil and the capital Baghdad, as well as the oil-rich province of Kirkuk, which is ethnically mixed.
The central government in Baghdad, which strongly opposes the referendum, sought control of the region's international border posts and airports on Sunday, in anticipation of Monday's vote.
READ MORE: Tensions rise in Iraq ahead of Kurdish referendum
Iraq's government has also called on foreign countries to stop importing oil from the Kurdish region and to deal with them instead.
In a televised address on Sunday, Iraq's Prime Minister Haider al-Abadi warned of the dire consequences of the vote and vowed to never accept the disintegration of Iraq.
"This is an unconstitutional decision against the social fabric of our citizens. We will not recognise the referendum, nor its results," Abadi said.
"We will take follow-up steps to protect the unity of the country and the interests of every citizen living in a unified Iraq."
Meanwhile, the President of Iraq's Kurdish regional government, Masoud Barzani, has defended the decision to hold the referendum.