Russia and Turkey concluded the Sochi agreement in the Russian city of Sochi near the Black Sea in September 2018. One of the most important clauses was “the establishment of a demilitarized zone in the Idlib governorate in northwestern Syria” to stop the clashes between the Syrian regime forces and the opposition factions.

However, this agreement did not hold for long. A military escalation at the end of April 2019 saw Syrian regime forces — backed by Russian air cover — launch an attack on northwestern Syria. The regime managed to advance to Maarat al-Numan in southern Idlib province, a clear breach of Article 2 of the Sochi agreement, which stipulates, “The Russian Federation will take all necessary measures to ensure that military operations and attacks on Idlib will be avoided and that the existing status quo will be maintained.”

The escalation caused the displacement of more than 400,000 people between April and October 2019. By March 2020, these numbers had increased to more than 1.3 million.

On March 3, Ankara and Moscow agreed to a cease-fire in northwestern Syria, and the two sides began conducting joint patrols March 15. The Russian-Turkish patrols are conducted on the M4 highway that connects the city of Aleppo in northern Syria to Latakia, which is located on the Syrian coast in the west. This highway is of high priority for the Syrian regime and its allies, as it is a vital route between two major cities controlled by the regime.