The Iraqi Civil Aviation Authority told global flight operators that all flights to and from Erbil and Sulaimaniya airports in Iraqi Kurdistan would be suspended from 6 p.m. Friday (11 a.m. ET).
The efforts of Kurds to attain their own Middle East homeland are ramping up after 92 percent voted for independence.
All foreign flights will stop at 6:00 local time (15 GMT) according to airport director, Talar Faiq Salih.
But travel to the Kurdish region will become harder if airports in Erbil and Sulaimaniya are closed to worldwide flights.
"They will be able to go to Baghdad, Basra or Najaf as transit points", he said.
The Kurds, whose borders with Turkey, Iran and Syria remain open, have condemned the flight suspension as "collective punishment".
Press TV has interviewed Adam Garrie, managing editor of theduran.com from London, and Joe Lauria, an author and independent journalist from Cairo, on the situation in Iraq's Kurdistan Regional Government (KRG). It also called for the deployment of forces to areas that had been under Iraqi government control before Islamic State (IS) forces captured Mosul in June 2014.
Prime Minister Haider al-Abadi's ultimatum came the day after the vote and ahead of the release of official results.
Iraqi Kurdistan held the referendum on Monday, in defiance of worldwide opposition.
"We can also close the Irbil International Airport to domestic flights, to Baghdad and Najaf".
Mr Barzani said the referendum would not draw borders, and that afterwards there could be talks with Baghdad for a year or two. Tillerson urged Iraqi Kurdish authorities to respect Iraq's central government.
"We have consulates, global staff, worldwide companies, so it's going to affect everyone", Salih said. "We could have helped many more people if we stayed".
On June 7, 2017, Kurdish Regional Government president Masoud Barzani announced that the region had set September 25th, 2017 as the date for a referendum on independence. A similar demand had been made on Monday but there have been no signs of any deployment. Meanwhile, Iran conducted military exercises on the Kurdish border last week, and the Turkish parliament passed a bill reauthorising military intervention in Iraq.
Analysts have said it is unlikely Baghdad will take military action in response to the vote, especially as the top priority for its forces remains the battle against IS.
Sharjah-based Air Arabia says it will "temporarily suspend its flights" from Saturday in line with an order it received from the Iraqi Civil Aviation Authority.
Turkey has also warned against travel to the northern Iraqi cities of Dahuk, Irbil and Sulaimaniyah, citing security risks following the referendum.
So far the pipeline is operating normally despite Turkish threats to impose economic sanctions on the Kurdish autonomous region in Iraq.