Turkey says the Russian-backed Syrian offensive violates a truce deal between Moscow and Ankara. The advance has exacerbated Syria's humanitarian disaster and threatened Turkey with mass refugee flows.
Turkish President Recep Tayyip Erdogan is meeting with his Russian counterpart, Vladimir Putin, on Tuesday to discuss a Syrian military offensive against the jihadi-dominated province of Idlib, where Moscow and Ankara had set up a demilitarized zone.
Syrian troops backed by Russian airpower have advanced in recent weeks against jihadi forces in the last major rebel enclave in northwestern Syria, and encircled a Turkish military post.
The fierce fighting has all but unraveled a fragile truce deal struck in September by Russia and Turkey as the Syrian regime pushes north to gain control of strategic highways connecting the government-controlled cities of Aleppo and Hama and the regime's Alawite heartland in Latakia on the Mediterranean coast.
Last week, a Turkish military convoy heading to an observation post in Idlib came under attack in an air raid conducted either by the Syrian government or Russian warplanes. The airstrike killed three civilians and wounded a dozen more. The Turkish Defense Ministry "strongly condemned" the August 19 attack and said it ran counter to "existing agreements as well as our cooperation and dialogue with Russia."
Turkey is a major backer of some rebel groups in Idlib, which is dominated by jihadi factions led by Hayat Tahrir al-Sham, al-Qaida's former Syria affiliate.
Hayat Tahrir al-Sham is not part of the September de-escalation agreement and has carried out attacks on forces allied to the Syrian government, as well as Russia's Hmeimim air base using drones and missiles.
Syrian White Helmets risk death in Idlib
Idlib is home to about 3 million people — half of whom have been displaced from other parts of Syria. Nearly a half million people have been displaced since the Syrian offensive began in late April. Many have fled to crowded camps on the Turkish border or are now sleeping out in the open.
The September truce deal between Russia and Turkey envisioned the creation of a demilitarized buffer zone between regime- and rebel-controlled areas and an as-yet-unfulfilled commitment by Turkey to isolate and combat jihadi groups. Turkey has 12 military observation posts ringing Idlib province.
The agreement was reached amid international concern that an offensive by the Syrian regime would send a flood of refugees and hardened extremist fighters to Turkey — which already hosts more than 3.5 million refugees — and potentially onward into Europe.