ISTANBUL -- Iranian Foreign Minister Ali Akbar Salehi has paid a visit to Ankara as Turkish armed forces continue their incursion into neighboring northern Iraq to root out the PKK Kurdish rebel group.
His appearance in the Turkish capital comes two days after a deadly attack by the PKK killed 24 Turkish soldiers. At a press conference with his Iranian counterpart, Turkish Foreign Minister Ahmet Davutoglu, the two leaders said they agreed to collaborate in fighting the PKK.
"Our joint determination to struggle against the PKK and the PJAK will continue in the strongest way," Davutoglu said, referring also to the Iranian Kurdish rebel group Party for a Free Life in Kurdistan (PJAK), which Tehran regards as a terrorist organization. "From now on, we will work together in a joint action plan until this terrorist threat is totally eliminated."
But behind the smiles and promises of support questions remain over Tehran's commitment. There are rising bilateral tensions over Ankara's support of the opposition against its key ally, Syrian President Bashar al-Assad.
Tehran also is still smarting over Ankara's decision to allow a NATO radar to be placed on Turkish territory as part the trans-Atlantic alliance's antimissile system, which is primarily aimed at Iran. (Earlier this week, the Iranian Foreign Ministry dismissed claims by Davutoglu that Tehran had agreed to the deployment.)
But Tehran has limited leverage over Ankara
other than to play the Kurdish card, says Iran watcher Jamsid Assadi of France's Burgundy Business School.
"The biggest lever, they think, is the question of Kurds," Assadi says. "It has always been a question of pressure between Iran, Iraq, and Turkey. Sometimes they use the question of [the] Kurds to have some influence on each other's diplomacy and policy. I think it could be now one of the possibilities for the Islamic Republic."
Concern that Tehran could be playing the Kurdish card have been growing after reports over the summer said Iranian forces had captured the deputy leader of the PKK rebels, Murat Karayilan, who was believed to be based in the Qandil Mountains on the Iran-Iraq border.
Tehran strongly denies the allegation, but suspicions persist in the Turkish media that Karayilan was captured then released.
In Ankara, Iranian Foreign Minister Salehi again denied the claim.
A former Turkish diplomat to Iran and current professor of international relations at Istanbul's Kultur University, Murat Bilhan, says it would not be the first time Tehran has used the PKK against Turkey.
"Iran has used the PKK in different times against Turkish interests, and it very aggressively and offensively used PKK -- and we were criticizing them for protecting or supporting or any way condoning, having not cooperated with Turkey against terror and so forth," Bilhan says. "So we had grievances against Iranians in the past. But not anymore, because now Iran is also hurt by them."
The Iranian Kurdish PJAK is closely connected to the PKK.
Last summer, Iranian forces launched a massive offensive against PJAK, which ended amid reports that Tehran had agreed a cease-fire, much to Ankara's displeasure. But Syria may present an even greater concern to the Turkish government.
Turkish Prime Minster Recep Tayyip Erdogan's strong support for the Syrian opposition has led to fears that Assad could also wield Kurdish discontent against Turkey, says Semih Idiz, the diplomatic correspondent for the Turkish daily newspaper "Milliyet."
"We understand Bashar al-Assad is now trying to coop the Kurds," Idiz says. "What that will mean and how that will translate into the situation in Syria, I think Ankara is watching very closely."
It would not be the first time the PKK has played a role in pressure from Damascus on Turkey. Syria hosted PKK leader Abdullah Ocalan until 1999, when Turkey threatened to invade. The incident prompted his expulsion and eventual capture and imprisonment in Turkey.
The end of Syria's support for the PKK and its crackdown on its operations were the foundations of a rapid rapprochement with Turkey. But with that thaw seemingly over, former Turkish diplomat and visiting scholar to Carnegie Europe Sinan Ulgen warns there are considerable risks for Turkey.
"Syria has its own Kurdish minority, and we know that majority of the PKK fighters outside of the Turkish borders of are Syrian origin," Ulgen says. "There is the risk there that if the political control vanishes, the PKK can start to use that land the way that it was able to before 1999. "
That connection came to the fore in the latest PKK attack, on October 19. Turkish media is full of reports that it was a Syrian Kurdish commander who ordered the attack.
Before the attack, Selahattin Demirtas -- the co-leader of Turkey's main pro-Kurdish party, the BDP -- warned in a newspaper interview that Assad could be attempting to manipulate ethnic animosities to check Turkey.
"The threats of [President Bashar] al-Assad's regime to Turkey should not be underestimated," Demirtas said. "He has given a message: 'We have religious and ethnic differences, so does Turkey. If we have domestic disturbances, then so will Turkey.'"
But this month's assassination of Mesh'al al-Tammo, a prominent member of Syria's Kurdish minority, which was widely blamed on Assad's security forces, alienated many Syrian Kurds.
The killing could well signal the end of Assad's half-hearted attempts to keep the ethnic minority out of the opposition movement.
But even if Syria and Iran aren't actively using Kurdish resentment, the deepening conflict with the PKK has seriously hurt Ankara's increasingly assertive and ambitious aspirations of being a regional, or even global, player, according to political scientist Cengiz Aktar of Istanbul's Bahcesehir University.
"It might have implications on the ambitions of Turkey in the region -- Turkey is now supporting the Syrian opposition and giving advice everywhere from Egypt to Tunisia," Aktarin says. "I think people will be tempted more and more to say, 'Please fix your problems at home first before teaching lessons to others.' After the attacks, both the prime minister and minister of foreign affairs had to cancel their foreign visits, so Turkey needs more than ever on its own problems."
Damascus may already be reaping the rewards of Ankara's distraction. The Turkish prime minister was expected this week to visit Turkish camps of Syrian refugees, after which he was due to announce sanctions against Damascus.
That, for now at least, appears to have fallen off the agenda.