Bolani's visit follows the signing of a memorandum of understanding between Iraqi Prime Minister Nuri al-Maliki and his Turkish counterpart Recep Tayyip Erdogan in August that paved the way for the agreement.

Ankara has threatened a military incursion to strike at bases of the Kurdistan Workers' Party (PKK) in neighbouring northern Iraq if Baghdad and Washington fail to curb the rebels, who notably stepped up attacks inside Turkey this year.

"We do not accept any person or a group that is against Turkey," Bolani said at the airport, adding that Baghdad was willing to improve bilateral relations in all fields, Anatolia news agency reported.

Turkey says the PKK, listed as a terrorist group by Ankara, Washington and much of the international community, enjoys free movement in northern Iraq, where it obtains weapons and explosives.

Turkey has accused the forces of Massud Barzani, who heads the autonomous Kurdish administration there, of tolerating the group and even providing it with weapons, possibly including ammunition received from the United States.

Observers here doubt whether Maliki's embattled government, which has virtually no authority in northern Iraq, can persuade the Iraqi Kurds to act against the PKK, whose 23-year armed campaign for self-rule in southeast Turkey has resulted in more than 37,000 deaths.

During his two-day visit, Bolani was expected to meet with senior Turkish officials from the interior ministry, the general staff and the intelligence services.

In June, the Turkish army said there were some 5,000 PKK rebels in total, an estimated 2,800 to 3,100 of them based in northern Iraq.

The PKK has notably stepped up its attacks in the east and southeast of Turkey this year and, in response, the army has reinforced its units in the region and amassed troops on the border with Iraq.

Washington has warned Ankara against an incursion into northern Iraq, wary that it may destabilise a relatively peaceful region of the country and fuel tensions between Turkey and the Iraqi Kurds, staunch US allies.