More refugees, defeat for friendly opposition forces and diminishing hopes for 'safe zones' make Syrian regime's Aleppo advance a nightmare for Ankara.

As if the housing of 2.5 million Syrian refugees, a dangerous escalation with Russia, and jitters over a string of Kurdish victories on its southern border were not enough, Turkey woke to another nightmare this week as thousands of Syrians massed at the Turkish border.

The new exodus is a result of the surprisingly swift advance of Russian-backed regime forces towards Aleppo this week. Aided by an intense Russian air campaign, forces loyal to Syrian president Bashar el-Assad were able to break the three-year rebel siege of Shia villages Nubul and Zahra and encircle Syria’s second largest city, Aleppo. While no longer the bustling commercial centre that it once was, Aleppo and the surrounding villages are still home to half a million Syrians and remain the nerve centre for Syrian opposition activity.

Overnight, 20,000 Syrians had fled to the Bab al-Salam (Öncüpinar) border crossing on Friday, with Turkish and United Nations officials predicting tens of thousands more to come if the fighting in Aleppo intensifies.

While Turkey has not yet allowed in the new wave of refugees, Prime Minister Ahmet Davutoğlu pledged on Friday that Turkey would not leave them without food or shelter. Turkish government aid agencies are scrambling to build capacity, identify vacancies in existing refugee camps in the area and provide a registration system for the newcomers. Plans are underway to open the border crossing on Monday, which incidentally coincides with a snap visit by German Chancellor Angela Merkel to Ankara to discuss the joint action plan on refugees between Turkey and the European Union.

But the sudden inflow of new refugees is only part of the problem for Ankara. A larger issue is the fact that the carefully-designed Russian-Syrian offensive this week has cut off the main supply routes from Turkey into the rebel-held areas of Aleppo. The coterie of Sunni rebel groups – from moderate wings of the Free Syrian Army to the more jihadist Ahrar al-Sham and Jabhra al-Nusra - control an area running from eastern Aleppo towards the Turkish border. The Russian-Syrian offensive has made east-west cut across the rebel-held areas, effectively blocking the opposition from reaching their supply lines south of the Turkish border.

This is a political nightmare for Ankara. The move has cut off Turkey’s access to the Sunni rebel groups and, in the wake of a new round of international diplomacy, aims to undercut Turkey’s ability to influence the dynamics on the ground.

Turkey had long argued for a “safe zone” north of Aleppo, stretching towards the Turkish border, but since collapse of Russian-Turkish relations since the downing of a Russian Su-24 in November, the Russian air force has effectively turned the border area into an “unsafe zone” for ordinary civilians and armed militias. Much to Ankara’s embarrassment, Russians have been aggressively patrolling the border areas for months now, deliberately targeting Turkey-backed Sunni militia groups to the west of Aleppo, as well as jihadist groups like Jabhat al-Nusra and Ahrar al-Sham both in Idlib and in the Aleppo provinces. Turkish President Recep Tayyip Erdoğan made another attempt this week to reach his old friend and Russian counterpart, Vladimir Putin, but according to Erdoğan’s spokesman, Moscow is refusing to take the call.

Both the regime and the opposition forces have long been talking about the imminent “battle of Aleppo” in apocalyptic terms. But for Ankara, this is a triple disaster marking a military defeat for the friendly opposition forces, a political defeat for its “safe zone” proposals and a humanitarian problem with new refugees.

Over the next few days, Turkey will likely continue to highlight its own critical role in the refugee crisis and call on the international community, including Washington, to reconsider “safe zones” inside Syria. On a tour in Latin America this week, Erdoğan continued to talk about a no-fly zone and establishing “new cities” inside the Syrian border as the best solution to the refugee issue.

But for now, he has to deal with the fallout from the Russian jets over the Aleppo.

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