Iraq plans to take control of the borders of its autonomous Kurdish region "in coordination" with Iran and Turkey, the Iraqi defence ministry has said.

Published on Friday, the ministry's statement did not give more detail or indicate specifically whether Iraqi forces were planning to move towards the external border posts controlled by the Kurdistan Regional Government (KRG) from the Iranian and Turkish side.

The move to seize the border posts is a response to a Kurdish referendum on Monday that produced a vote in favour of secession from Iraq.

Following the vote, Iraq, Iran and Turkey demanded that the KRG relinquish control over its external border crossings with Turkey, Iran and Syria.

Backed by Ankara and Tehran, the Iraqi government has demanded that the Kurdish leadership cancel the result of the referendum or face the prospect of sanctions, international isolation and possibly a military intervention.

The KRG refused to relinquish control of its border crossings, Erbil-based TV Rudaw said on Friday, citing a Kurdish official.

The Iraqi defence ministry said the implementation of central government decisions to take over management of all the border posts and airports was "going as planned in coordination with the relevant authorities and neighbouring countries, and there is no delay in the procedures".

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Iraq's state television said an Iraqi military delegation had visited the Kurdish region's border from the Iranian side. An Iraqi force is also deployed on the Turkish side of the border as part of joint drills with the Turkish army.

International flight embargo

Earlier on Friday, a ban imposed by Iraq's central government on international flights to its Kurdish region went into effect after the KRG rejected a demand to hand over control of its international airports in Erbil and Sulaimaniyah.

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.

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.

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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."

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, Rudaw TV said.