Ths US has repeatedly attempted to persuade the Iraqi Kurdish Regional Government (KRG) to delay the referendum, fearing further friction between Irbil and Baghdad could derail the fight against ISIS.
Early estimates Tuesday indicated that more than 90 percent of Iraqi Kurds voted in support of independence - with turnout estimated at 71 percent.
Iraqi Prime Minister Haider al-Abadi also called on foreign states to stop cooperating with the KRG on issues in the oil sector.
Masoud Barzani, President of KRG, said on Sunday, that he would seek talks with Baghdad on how to implement the outcome of the poll.
The official results are expected to be announced on Thursday.
"This referendum decision, which has been taken without any consultation, is treachery", he blustered.
Turkey fears that the emergence of an independent Kurdish state on its border will stoke separatist feeling in its own Kurdish minority.
PM Abadi says Baghdad will not discuss results of Kurdish independence referendum, calling it "unconstitutional". The U.S. government provided Iraqi Kurdish military forces with almost $480 million in aid in FY2017, and in May, President Donald Trump authorized the Defense Department to equip Syrian Kurdish forces to fight Islamic State militants - despite Turkey's objections.
Along with Iraq's central government, Turkey, the U.S., Iran and the United Nations spoke out against the referendum, saying it would distract from the ongoing fight against Daesh and further destabilize the region.
The disputed areas are the oil-rich province of Kirkuk, as well as parts of Nineveh, Diyala and Salaheddin provinces.
The voting is open to all registered residents, Kurds and non-Kurds, in the Kurdish-held areas in northern Iraq aged 18 or over, according to the referendum commission.
The UN - as well as the United States and other Western powers - expressed concern that the referendum would pull attention away from the efforts to defeat IS.