Defense Minister Hulusi Akar and his Russian counterpart Sergei Shoigu discussed recent developments in Syria's Idlib in a phone call Wednesday.

The ministers discussed recent developments and regional security issues in Idlib buffer zone, Defense Ministry said in a written statement.

Idlib and some surrounding areas are the last major opposition bastion in Syria, where the Russian-backed regime has in recent months retaken much of the territory it had lost since the civil war erupted in 2011.

It had threatened an assault on opposition territory, home to around 3 million people, but a deal for a buffer zone around it was reached in September between Ankara and Moscow.

After a Sept. 17 meeting in Sochi between President Recep Tayyip Erdoğan and his Russian counterpart Vladimir Putin, the two sides agreed to set up a demilitarized zone — in which acts of aggression are expressly prohibited — in Idlib province.

According to the terms of the deal, opposition groups in Idlib will remain in areas in which they are already present, while Russia and Turkey will conduct joint patrols in the area with a view to prevent a resumption of fighting.

Syria has only just begun to emerge from a devastating conflict that began in 2011 when the Assad regime cracked down on demonstrators with unexpected ferocity.