ERBIL, Iraq — Iraq’s prime minister, angered by a vote on independence by his nation’s Kurdish minority, has given the country’s Kurdish region until Friday to surrender control of its two international airports or face a shutdown of international flights.

Kurdish leaders in northern Iraq had antagonized Iraq, Turkey and Iran by holding the referendum on Monday. The results have not yet been announced, but the Kurdish Regional Government said on Tuesday that the vote had gone overwhelmingly in favor of independence from Iraq.

A “yes” vote would not lead to an immediate declaration of independence for the semiautonomous region, but it would direct the regional government to begin the process of creating an independent state, including negotiating a separation with Baghdad.

Iraqi officials have called the referendum unconstitutional and have refused to negotiate with the Kurdish leadership. The Iraqis fear losing a third of the country and a major source of oil should Kurdistan break away.