Tension is escalating rapidly west of the Euphrates River, especially in the area of Syria's Afrin canton controlled by the Kurdish People’s Protection Units (YPG), and at Idlib, controlled by a motley collection of outfits mostly backed by Turkey.

Last week, as the Turkish army continued to amass forces in the triangle of Kilis in Turkey, and Jarablus/al-Bab/al-Rai in Syria, Turkish 155 howitzers began shelling YPG targets southwest of Azaz and north of Tel Rifaat. The YPG returned fire with its 81 mm mortars at Free Syrian Army (FSA) targets in the triangle. Local sources told Al-Monitor there have been occasional clashes between the YPG and the FSA east of Tel Rifaat over the past two weeks.

The YPG issued a statement June 30 saying it plans to take from Turkey the area between Azaz and Jarablus. It offered no timeline. 

Ankara’s priority target in northern Syria is the YPG. Turkey aims to prevent the creation of a Kurdish or Kurdistan Workers Party (PKK) corridor that would begin at PKK headquarters in the Qandil Mountains and extend to Afrin canton in the west via Shengal, and the cantons of Jazeera and Kobani.