Iran-Turkey ties tested by Assad's downfall in Syria

The sudden collapse of Bashar Assad's regime in Syria changed the geopolitical landscape of the Middle East overnight. Iran and Turkey, who for years have maintained a delicate geopolitical balance, are now faced with competing interests in a post-Assad Syria.

Despite years of collaboration — particularly on Turkey's economic support to circumvent international sanctions on Iran— relations between Iran and Turkey appear to be fraying.

On Wednesday, Iran's Supreme Leader, Ayatollah Ali Khamenei, delivered a veiled critique of Turkey, accusing an unnamed "neighboring country" of conspiring with the US and Israel to topple the Assad regime.

Competing strategies in Syria

Turkey has long provided support for anti-Assad rebel groups, including the Hayat Tahrir al-Sham (HTS) Islamist militant group that led the march to Damascus.

However, Turkey's primary interest in Syria has been to create a buffer zone and a bridgehead to fight Kurdish groups in northern Syria.

Since 2016, Turkey has occupied chunks of northern Syria. In 2017, it helped create a coalition of armed opposition groups called the Syrian National Army (SNA) to counter Kurdish militants.

The success of opposition groups against Assad with Turkey's long-standing support points to Ankara potentially having more influence in Syria going forward.

In post-Assad Syria, Turkey ultimately wants to prevent Kurdish interests from taking root in a new Syrian government.

Henri J. Barkey, an adjunct senior fellow for Middle East studies at the US Council on Foreign Relations, wrote in a recent article that the "single most crucial aim" for Turkey in Syria remains the eradication of the Syrian Kurdish group, the Syrian Democratic Forces (SDF).

Barkey said Turkey fears that "Syrian Kurds would cut a deal with any central government in Damascus to achieve an autonomous status just like Iraqi Kurds did following the Iraq war."

For Iran, the Assad regime was a critical strategic ally in the Middle East, and as Turkey is poised to gain influence, Iran's ability to project power in the region has been steadily diminishing.

Omid Shokri, an international relations expert from Istanbul, told DW that Iran "might consider supporting Syrian Kurdish groups to exert pressure on Turkey."

Wider regional implications

Ahmad Vakhshiteh, a senior lecturer at RUDN University in Moscow, said he believes that recent developments in Syria have shifted the balance of power in Turkey's favor.

Vakhshiteh told DW that Ankara could capitalize on Tehran's current vulnerabilities to advance its wider geopolitical aims.

This includes support for a land corridor connecting the land-locked Azerbaijani exclave Nakhchivan to Azerbaijan. Nakhchivan borders both Turkey and Iran.

Turkey is in favor of the land corridor that would connect it with Turkic regions. Iran has raised concerns that Azerbaijan could use it to block Iran's access to Armenia.

He also highlighted Russia's lack of motivation to intervene in Syria and in Nagorno-Karabakh, which has allowed Iran's regional rivals, including Turkey, to gain the upper hand.

"The notion that Turkey has expanded its influence in Syria with Russia's approval is somewhat exaggerated. Countries have long been analyzing and planning based on their national interests, and this is not a new development," Vakhshiteh said.

Turkey's economic lifeline to Iran

For years, Turkey has been a critical partner in helping Iran circumvent international sanctions over Tehran's nuclear program.

Along with the UAE, Turkey has facilitated trade and provided essential goods to Iran.

Official data from Iran's customs authority revealed that trade volume between the two countries reached approximately $10 billion in the first ten months of this year, with ambitions to triple this figure within five years.

However, escalating tensions could threaten this economic lifeline.

Turkey is also a popular destination for Iranian property investments, consistently ranking among the top three buyers of real estate in Turkey.

These ties will be tested as the future of leadership in Syria  takes shape. 

Edited by: Wesley Rahn