An Iraqi Kurd flag flies in Istanbul, and may help Erdogan win power poll

When Massoud Barzani, the president of Iraq's Kurdish region, arrived at Ataturk airport in Istanbul on 26 February, he was greeted by a rare sight: the raising of the red, yellow and green flag of his government next to the red and white of Turkey.

It was not the first visit by the president of the Kurdistan Regional Government (KRG) to Turkey. Nor was it the first time that the KRG flag had been displayed officially in Turkey: indeed, it was first placed next to the flags of Iraq and Turkey during a meeting in Ankara in 2015.

But it was the first time it was flown in public alongside the Turkish flag. Turkey has seen many changes over the past year and faces more with the upcoming April referendum on constitutional changes. The flying of the KRG flag sparked the first rift in the alliance to support President Recep Tayyip Erdogan's highly controversial plans for an executive-style presidency.

Devlet Bahceli, the leader of the far-right Nationalist Movement Party (MHP) – which of late has been supporting Erdogan and the Justice and Development Party (AKP) – was livid.

He launched a tirade against the Turkish prime minister, Binali Yildirim, demanding an explanation as to who allowed that "rag" to be hoisted on Turkish soil.

'Who allowed this so-called flag to be raised? Is this part of a planned conspiracy?'

- Devlet Bahceli, MHP leader

"It is a scandal, an aberration, a disgrace," he shouted in parliament while addressing his party's MPs. "Who allowed this so-called flag to be raised? Is this part of a planned conspiracy?"

Yildirim's response was uncharacteristically timid and interpreted by observers as seeking to calm the situation.

"That [raising the KRG flag] was just following diplomatic protocol," Yildirim told politicians from his own ruling Justice and Development Party (AKP). "The Iraqi central government accepts the KRG as a federal autonomous region with its own flag."

Erdogan remained conspicuously silent on the matter. And with good reason: the row could play into his hands, weakening both his alliance partner and his opponents in the referendum, while potentially delivering Kurdish votes.

Why Erdogan needs MHP support for vote

Turkey has endured a mixed relationship with Barzani's Kurdistan Democratic Party (KDP), the most conservative and Islamist among the mainstream Kurdish parties in the region and which forms the backbone of the KRG.

But in recent years, Ankara and Erbil have developed a strong working relationship based on mutual security and economic interests.

Yet for many in Turkey, especially in the right-wing MHP, there is little distinction to be made between northern Iraq's Kurdish groups and Turkey's Kurdish separatist movement.

To them, the autonomous KRG is a strong symbol of all that could potentially go wrong for Turkey, including the formation of a Kurdish state, whether it be autonomous or independent.

The raising of the KRG flag raised the ire of the MHP's nationalists because it resembles other Kurdish flags - even that of the Kurdistan Workers' Party (PKK), with whom Turkey has been at war since 1984 and which is designated as a terrorist organisation.

And Erdogan needs the support of the MHP for the vote. It was Bahceli who, in the wake of July's failed coup attempt, completely reversed his previous position and said that his party would back the AKP plan for governance.

• Read: Will Erdogan be president until 2034?

His decision divided the MHP: several highly influential party members were either expelled or else broke with the party line to campaign for a "no" vote.

The MHP has since tried to say that the KRG flag incident does not mean it will withdraw support for the proposed changes – but this is likely to harm the party's campaign even more.

Even right-wing newspapers, which had previously targeted Bahceli, praised him for his remarks on the KRG flag. Any softening of his position is likely to play into the hands of his rivals.

One of those is Umit Ozdag, a former deputy leader of the MHP, who was expelled from the party in November. Ozdag has questioned the AKP's motives for flying that airport flag and hinted at a behind-the-scenes deal.

Translation: "What is the AKP repaying Barzani for by hoisting the flag? The flags of federal regions are not flown."

But Mazhar Bagli, a former AKP politician and current academic at Konya's Karatay University, told Middle East Eye the AKP-MHP alliance will not be harmed because it isn't a multi-issued one.

"There might be some unpleasantness between the two parties but there is no chance of a rift because the alliance is a single-issue alliance and that issue is the shift to the executive presidency system," said Bagli. "Neither party has compromised or bargained on any of its other positions and both are clear on this."

Flying the flag, wooing the vote?

Some commentators have said that the hoisting of the flag might have been an AKP gesture to the country's Kurdish constituents, enticing them to vote yes in the referendum.

Ethnic Kurds comprise 15-20 percent of Turkey's population - and their votes can be a determining factor in what is being seen as a tight contest.

In one poll conducted in mainly Kurdish-populated southeastern provinces during 7-12 February, 57.4 percent said they would vote no while the yes count stood at 25.1 percent.

Many of Turkey's Kurds are disenchanted with the AKP after its sharp swing to the right in recent years and its adoption of nationalist stances. The severe clashes in the southeast since 2015 and the imprisonment of politicians from the pro-Kurdish People's Democratic Party (HDP) also hit the popularity of the AKP.

• Read: How the Kurds became Turkey's own refugees

Sahismail Bedirhanoglu, the Diyarbakir-based head of the southeastern industrialists and business association, told Middle East Eye that the flying of the KRG flag would have been a "nice" symbolic gesture for Kurds that, initially at least, would not have influenced their vote.

But the reaction from the 'No' camp and the right has made a crucial difference.

"It was mostly viewed as a nice recognition and valuing of Kurdish symbols with probably no impact on voting tendencies," he explained. "But the reaction of the 'no' camp has certainly alienated many Kurds who are now inclined to vote yes in favour of the AKP's presidential plan."

Turkey wants to show the world that it has no problem with any ethnicity, even with a Kurdish administration

- Mazhar Bagli, former AKP politician

Other commentators have hinted at a deal between Barzani and the Turkish government to tackle what Ankara regards as the growing problem of the Syrian-Kurdish Democratic Union Party (PYD), an extension of the PKK in Ankara's view, in northern Syria.

They have backed up these claims by pointing to clashes between the Barzani-supported KDP peshmerga forces and PKK-backed forces along the Iraqi-Syria border.

But Bagli dismisses both sets of claims and said the flying of the KRG flag could only have one message.

"Turkey wants to show the world that it has no problem with any ethnicity, even with a Kurdish administration," he said.

"It wants to show the world that it is only against groups relying on terror to achieve their goals, such as the PKK and its affiliates."

This article is available in French on Middle East Eye French edition.