“It’s too late to talk about delaying the referendum,” Mr. Barzani said in a statement released by his office in Erbil on Saturday.
“It’s not my decision anymore, he added. “It’s a decision for the people.”
In a defiant speech on Friday evening to 40,000 Kurds in Erbil chanting “Bye-bye Iraq,” Mr. Barzani said of Turkey and Iran: “You have punished us for one hundred years. Are you not tired yet?”
Both Turkey and Iran fear that an independence move by Iraqi Kurds could set off unrest among their own Kurdish minorities.
Baghdad considers the vote illegal and unconstitutional, and Prime Minister Haider al-Abadi of Iraq has said his government is prepared to use military force if the referendum provokes violence. A delegation of Kurdish leaders traveled to Baghdad on Saturday to discuss the referendum with Iraqi officials.
Ali al-Alaq, a member of Iraq’s Parliament who has led talks with the Kurds, said in an interview that the discussions would continue over the weekend. But he said negotiations would end if the vote were conducted on Monday.
Kurdish officials said voting had already begun Saturday among Iraqi Kurdish expatriates in Germany, Denmark, Britain and Switzerland. Some waved the Kurdistan flag.
The United States and most of the international community have opposed the referendum, saying it could unleash ethnic conflict, break up Iraq and undermine the American-led campaign against Islamic State militants.
Iran, the Kurdish region’s eastern neighbor, has threatened border closures, prompting some Kurds to stockpile food and supplies.
Kurdish officials in Erbil, Iraqi Kurdistan’s capital, said they were continuing to talk on Saturday with American officials. The Kurdistan Regional Government has said it would scrap the referendum only if the United States provided an ironclad guarantee of a path to independence within a specified time.
The United States has urged Kurds to cancel the vote and begin negotiations with Baghdad, facilitated by Washington. Kurdish leaders say they want a public mandate from the Kurdish people before negotiating independence.
After the Americans established a no-fly zone in 1991 that protected Kurdish areas from attacks by Saddam Hussein’s troops, the Kurds have carved out an autonomous region with its own government, parliament and military. Kurdish fighters known as the pesh merga have played a central role, alongside Iraqi troops, in operations against the Islamic State.
The referendum would not lead directly to independence, but a strong “yes” vote would strengthen the Kurdish position in any negotiations with Baghdad. Rozh Nouri Shaways, leader of the Kurdish delegation in Baghdad, told reporters that Kurdistan was willing to negotiate with Iraq before and after the referendum.
Baghdad and Iraqi Kurdistan are locked in a longstanding dispute over contested areas, including oil-rich Kirkuk, seized by Kurdish fighters in 2014. Baghdad fears that the independence vote, which includes citizens of the contested areas, would strengthen Kurdish claims to those territories.
The ballot asks voters whether they want Kurdistan and the contested areas to become an independent state.
Kirkuk’s provincial governor, Najmaldin Karim, a Kurd, urged residents on Saturday to prepare to vote on Monday. “All the preparations have been made,” Mr. Karim told the Kurdish news agency Rudaw. He called the vote “historical.”
On Saturday morning, the police controlled by the Baghdad government withdrew from their posts in the city of Kirkuk and surrounding areas, according to local officials. They said that the police and government-paid school administrators had been directed by Baghdad not to assist with the referendum. Much of the voting is scheduled to take place at schools.
Kurdish officials said security officers from the Kurdistan Regional Government took over responsibility Saturday for security in the area.