It is only normal for "a minister bearing a red passport to visit the regional administration (in northern Iraq) and then travel to Kirkuk, 40 kilometres from (Arbil) to meet with his kinsmen," Erdogan told the ATV television station.

Kirkuk province is part of a swathe of disputed territory in northern Iraq that along with oil contracts are the two main points of contention between Baghdad and the Kurdish regional government in Arbil.

Turkish foreign minister Ahmet Davutoglu made an unannounced trip to Kirkuk last Thursday while on a visit to Arbil for talks with Iraqi Kurdish leader Masoud Barzani.

Davutolgu visited leaders of Kirkuk's Turkmen community, with which Ankara has long had close ties, as well as religious and historical sites including the city's Ottoman cemetery.

The Iraqi foreign ministry said that it was done without approval from Baghdad.

On Sunday, Erdogan said growing energy bonds between Turkey and northern Iraq were also a source of uneasiness for the Baghdad government.

The oil dispute between Baghdad and the Kurdish government in Arbil has worsened, with the autonomous region looking to ramp up oil production and export capabilities. The region has also cut off oil exports to Iraq in a payment row.

Adding to the controversy, Turkey has for months hosted Iraq's fugitive Sunni Arab vice president, Tareq al-Hashemi, who is wanted on charges of running a death squad and is being tried in absentia.

Turkish media recently reported that Hashimi was granted residence permit by Turkish authorities to avoid visa problems during his trips abroad but that was not confirmed by a Turkish foreign ministry spokesman contacted by AFP.