A ban on international flights into Iraq's Kurdish region has gone into effect after the central government in Baghdad retaliated against a vote for secession that has also drawn opposition from neighbouring countries.

Iraq's Kurds overwhelmingly backed a split from Baghdad in a referendum on Monday, defying foreign powers which fear the vote could lead to regional instability.

The ban came into force at 6pm (15:00 GMT) on Friday. Foreign airlines suspended flights to the region's Erbil and Sulaimaniyah, obeying a notice from the government in Baghdad, which controls Iraqi airspace.

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Domestic flights are still allowed, so travellers are expected to travel to the Kurdish region mostly via Baghdad's airport, which will come under strain from the extra traffic.

Erbil airport was busier than usual on Friday as passengers scrambled to catch the last flights out.

Al Jazeera's Hoda Abdel-Hamid, reporting from Erbil International Airport, said: "We saw many people throughout the day leaving ahead of schedule simply because they were afraid to be blocked here and not be able to return to their homes, or because they did not want to go through Baghdad to catch an international flight."

Talar Saleh, director of Erbil's airport, described the alternative for passengers to fly through Baghdad's airport as "difficult".

"First of all, Baghdad doesn't have transit flights," she told Al Jazeera, warning that the airport in the Iraqi capital will not be able to deal with growing numbers due to its size.

"They cannot cope with the increased number of passengers. There are also many people who are actually banned by Baghdad to go … [there] - so that's not possible," Saleh added.

The office of Iraqi Prime Minister Haider al-Abadi said on Friday that demands for the handover of the Iraqi Kurdish region's air and land outlets were designed to regulating the movement of people and goods, and preventing smuggling.



"The central government's control over these facilities are not aimed at starving the territory's people as some Kurdistan official claim," Abadi's office added in a statement.

But Al Jazeera's Abdel-Hamid said that people in the region had a different view.

"Many point to this exact move to say that this is exactly why the Kurdish authorities should go ahead with the … secession proceedings," she said.

Dozens of the Kurdish region's people Friday gathered outside the Erbil airport in protest against the ban. Some demonstrators waved the territory's flag.

Effects of ban

Maintaining the travel curbs is likely to discourage visits by businessmen and Kurdish expatriates and affect a host of industries, including hotels, financial services, transport and real estate.

More than 400 Kurdish travel and tourism companies are directly affected by the flight ban and 7,000 are jobs at risk in the sector, Erbil-based Rudaw TV said.

Turkey, which has already threatened economic sanctions and a military response to any security challenges posed by the referendum result in neighbouring northern Iraq, has maintained a drumbeat of opposition to the Kurdish vote.

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After talks in Ankara with Russian President Vladimir Putin on Thursday, Turkish President Recep Tayyip Erdogan said the referendum was illegitimate.

He added that Russia and Turkey agreed that the territorial integrity of Iraq must be preserved.

The two countries have strong commercial ties with the semi-autonomous Kurdish region in Iraq. But the vote has alarmed Ankara as it battles a separatist rebellion from its own large Kurdish minority.

While Turkey has threatened to cut off the Kurds' oil export lifeline - a pipeline that runs through Turkish territory - Ankara has so far mostly held back from specific action against Iraq's semi-autonomous Kurdish region.

The Kurdistan Regional Government (KRG), meanwhile, refused to hand over control of its border crossings to the Iraqi government, as demanded by Iraq, Iran and Turkey in retaliation for the independence referendum.

Al Jazeera's Andrew Simmons, reporting from Turkey's border with Iraq as the flight ban went into effect, said the Habur border gate was the only way into Iraq's Kurdish region.

"This is the only means by which Turks can get across the border into Kurdistan Iraq," he said, adding that dozens of flights a week between the two areas had been "completely halted".

"The question now is will this the only land route from Turkey be closed? President Erdogan is considering it, however, it's a big deal if it happens because it will cut off the line life for Iraqi Kurds in terms of food, construction materials, medicines and a whole series of things," Simmons said.

"Furthermore, it will also damage the Turkish economy."

Turkish Prime Minister Binali Yildirim said Ankara would target only those who decided to hold the referendum since Ankara would not make civilians living in northern Iraq pay the price for the vote.

Iran banned the transport of refined crude oil products by Iranian companies to and from the Iraqi Kurdish region.

The autonomous Kurdish region would, however, be able to resist an economic blockade, a World Bank official told Reuters news agency.

"It is self-sufficient in electricity and fuel supply as it has the oil and gas fields, the refineries and the power stations," the official said, speaking on condition of anonymity.

"It has also the land and the water resources to sustain a basic subsistence even if borders are shut completely."

Right to vote

The Kurds consider Monday's referendum to be an historic step in the generations-old quest for a state of their own, while Iraq considers the vote unconstitutional.

Iraqi Kurdish leader Masoud Barzani has said the vote is not binding, but meant to provide a mandate for negotiations with Baghdad and neighbouring countries over the peaceful secession of the region from Iraq. Baghdad has rejected talks.

The Kurds were left without a state of their own when the Ottoman Empire collapsed a century ago. Around 30 million live in Iraq, Turkey, Syria and Iran.

The Kurds say the referendum acknowledges their contribution in confronting the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) armed group after it overwhelmed the Iraqi army.