The cancellation of a visit to Turkey last week by Iran's foreign minister has brought increasingly tense relations between Ankara and Tehran into sharper focus. The two countries back opposite sides in the Syrian civil war and accuse each other of heightening sectarian tensions between Sunni and Shi'ite Muslims.
Bilateral tensions between Iran and Turkey are increasingly being fought by the two countries' pro-government media outlets. Iranian reports targeting Turkish President Recep Tayyip Erdogan and his daughter, Sumeyye, recently proved too much for Ankara, resulting in the abrupt cancellation of Iranian foreign minister Javad Zarif's planned visit to Turkey.
"It's serious. I think the reporting in Iranian media, particularly the state-controlled media, about Erdogan and his family, did upset the presidency," said international relations expert Soli Ozel of Istanbul’s Kadir Has University. "There is no doubt in Iraqi Kurdistan and in Syria they are at loggerheads, so maybe because of the presidency [criticism] this is now being made much more public than was the case before."
PKK adds to tensions
In addition to bilateral tensions and a deepening rivalry for influence in the Iraqi Kurdish region, the resumption of Ankara’s war against the main Kurdish rebel group, the PKK, could add to those tensions, says retired Turkish ambassador Murat Bilhan.
"Iran, from time to time, used the PKK issue as a tool to threaten Turkey. But presently Iran wants to use the PKK and other elements in Syria against the Islamic State. They are fighting successfully against ISIS. That is why Iran seems to be showing the picture that Turkey should not hit hard on the PKK movement," said Bilhan.
Ankara has in the past accused Tehran of failing to prevent the PKK from using its border to attack Turkey. Analyst Ozel warns that threat remains.
"Well if they cannot use the Iraqi one, it's good for them to use any path that they can use. So if the Iranian helps them use it, then it’s an asset for them. But I think it's really incumbent on Turkey to make sure it's not vulnerable ... that it does not give Iran any tools to play against it," said Ozel.
The threat of Iran tacitly, if not directly, supporting the PKK is another factor being cited by growing calls for a resumption of the peace process with the PKK. But for now those calls are being dismissed by Ankara.