A plane carrying Turkish Energy Minister Taner Yildiz to an energy conference in Iraqi Kurdistan has been denied permission to land by the central government in Baghdad.
A Turkish energy ministry official said the plane, which was en route from Istanbul to the northern Iraqi city of Arbil on Tuesday, was forced to land in Turkey's Kayseri, southeast of the capital Ankara.
The plane would not seek permission to land again and the minister would now not attend the conference, the official said.
It was not immediately clear why the minister's private aircraft had been denied permission and officials in Baghdad were not immediately available for comment.
Ties between Ankara and Baghdad have been strained for the past year since Shia Iraqi Prime Minister Nouri al-Maliki ordered the arrest of Sunni Vice President Tareq al-Hashemi, based on allegations that he ran death squads.
Turkey is now giving sanctuary to Hashemi.
Turkey accuses Maliki of sowing sectarian discord by trying to sideline his Sunni rivals while Maliki says it is Ankara that is stirring sectarian tension.
Both leaders have exchanged public insults and both countries have summoned each other's top diplomats over the past year in tit-for-tat manoeuvres.
Ankara has increasingly courted Iraqi Kurds as its relations with the Shia-led central government in Baghdad have soured.
Turkey is a major investment and trading partner for Iraq, especially for Kurdistan.