Turkish officials have made quite clear in recent weeks that they do not see eye to eye with Iraqi Kurds on several key issues - despite the growth of very cordial and cooperative bilateral relations.
In late March the provincial assembly in the city of Kirkuk voted for the Kurdish flag to be raised alongside the flag of Iraq in public buildings. A backlash followed from Ankara and Baghdad alike.
Turkish Foreign Ministry spokesman Hüseyin Müftüoğlu claimed it would "harm reconciliation efforts and destabilise and endanger Iraq".
Kirkuk's governor, Najmaldin Karim, a leading figure in Iraqi Kurdistan's major Patriotic Union of Kurdistan (PUK) party, responded by declaring: "No foreign country has the right to meddle in the affairs of Kirkuk city."
On April 4, Turkish President Recep Tayyip Erdogan told the Kurds to lower the flag.
"We don't agree with the claim 'Kirkuk is for the Kurds' at all," he said. "Kirkuk is for Turkmen, Arabs and Kurds, if they are there. Do not enter into a claim [that] it's yours, or the price will be heavy. You will harm dialogue with Turkey.
"Bring that flag down immediately," he went on to demand.
Turkish Prime Minister Binali Yildirim also said that raising the Kurdish flag over Kirkuk was a "wrong move".
"We are supporting the Iraqi government on this issue,"the prime minister stated. Baghdad refuses to permit the flying of Kurdish flags over official government buildings in Kirkuk, after a parliament motion put forward by Turkmen from Kirkuk was passed in the national legislature.
Kirkuk governor Karim said the Turkmens' motion in Baghdad was "a hasty decision" and "is not legal[ly binding]".
"We have no obligation to implement this decision," he stated.
|Bring that flag down immediately
- Turkish President Recep Tayyip Erdogan
Prime Minister Yildirim of Turkey, meanwhile, called ethnically-mixed Kirkuk "a Turkmen city".
Turkey has always presented itself as the guardian of Turkmen communities outside its frontiers. For years it has rejected any effort by the Iraqi Kurds to annex Kirkuk, claiming that such a move would endanger the Turkmen there.
The autonomous Kurdistan Regional Government has invariably responded to such claims over the years by declaring that the rights of all non-Kurdish residents in Kirkuk are upheld and protected.
Disagreements between Turkey and the KRG over the status of Kirkuk are not new. But Turkey's staunch opposition to the raising of the Kurdish flag in Kirkuk is noteworthy considering its relatively cordial relations with Iraqi Kurdish authorities.
Relations began to thaw back in 2010, with Turkey opening a consulate in Iraqi Kurdistan's capital city, Erbil.
Kurdish flags are, meanwhile, displayed during state visits by Kurdish President Masoud Barzani to Ankara. Recently the standard was even flown at Ataturk International Airport in Istanbul, a significant gesture on Turkey's part, which has been waging a war against Kurdish separatists in south-eastern Turkey for more than 40 years.
"Perhaps the KRG remains the only entity in our immediate region that Ankara feels at ease with," suggested Turkish journalist Cansu Çamlibel, a writer with Hurriyet.
Relations between the Turkish government and the Kurdistan Democratic Party (KDP) -one of the two most powerful political parties in KRG, the other being the PUK - are particularly friendly.
The PUK, however, is closer to Iran - which, incidentally, is also against the raising of the Kurdish flag in Kirkuk.
Iraqi Kurdistan imports large amounts of Turkish goods, ranging from food to consumer electronics, and has been independently exporting its oil via pipeline to the Turkish port of Ceyhan. Friendly relations with Turkey would be essential for any independent landlocked Kurdish authority for it to continue to earn the oil revenues upon which its economy has heavily relied.
The Turkish Air Force frequently bombs Kurdistan Workers' Party (PKK) fighters in the Qandil Mountains, within the boundaries of Iraqi Kurdistan. Ankara has also said it will militarily intervene against the PKK in the Sinjar region if the group does not leave the area.
Erbil also opposes the PKK's continued presence there.
The PKK reportedly believes that Turkey is preparing to attack them in the region in coordination with the KRG authorities.
Turkey's efforts to contain the Syrian Kurdish Democratic Union Party (PYD) have also not been hindered by the KRG. Ties between the PYD and the KRG have not been warm in recent years, at least partially because of the PYD's refusal to share power in Syrian Kurdish territories with the KRG-sponsored Kurdistan National Council (KNC).
|We do not think bringing this issue to the agenda is correct
- Spokesman for President Erdogan
Turkey's treatment of wounded KRG Peshmerga soldiers fighting the Islamic State group also demonstrates that it distinguishes the KRG from other Kurdish groups it forcibly opposes and frequently attacks.
These factors have not, however, necessarily translated into support for Iraqi Kurdish independence. Over the weekend the KDP and PUK met and announced they were preparing to hold a referendum on independence for Iraqi Kurdistan this year. Turkey unequivocally opposes this.
"We think this [referendum] would be a wrong step," said Ibrahim Kalin, President Erdogan's spokesman. "We do not think bringing this issue to the agenda is correct, at a time when there are several security risks at the highest levels."
Hurriyet's Çamlibel also noted that cordial relations fostered between Ankara and Erbil in recent years could be subject to "a litmus test" as they deal with such fundamental and contentious issues about which they both feel very strongly, and over which they do not want to compromise.
In essence, despite the thaw in relations, Turkey's red-lines in Iraqi Kurdistan have remained essentially the same.
While Turkey is unlikely to forcefully move against the Iraqi Kurds - as they seemed to be preparing to do on the eve of the 2003 US-led invasion of Iraq - Ankara might nevertheless seek to restrain Kurdish independence aspirations, as well as their claim to Kirkuk, by exerting diplomatic, and perhaps even economic, pressures against them.
In this regard, the more things have changed in the Ankara-Erbil relationship the more they have, in some fundamental respects, remained the same.
Paul Iddon is a freelance journalist based in Erbil, Iraqi Kurdistan, who writes about Middle East affairs.
Follow him on Twitter: @pauliddon