The situation in Syria will top the agenda at a meeting between Russia's President Vladimir Putin and Turkey's President Recep Tayyip Erdogan later on Wednesday.
The two sides were the cosponsors of a deal agreed to last year, to de-escalate the fighting in Syria's Idlib province. They have worked together despite backing opposite sides during the war.
But with the United States planning to pull out its troops, it's getting complicated.
Al Jazeera's Rory Challands reports from Moscow.
