The leaders of Russia, Turkey, Germany, and France are expected to discuss the political settlement in Syria, including plans to create a demilitarized zone in Idlib province, as well as other international issues.
Russian President Vladimir Putin, French President Emmanuel Macron, German Chancellor Angela Merkel and Turkish President Recep Tayyip Erdogan are expected to give a joint statement in Istanbul following a meeting in the city.
The multilateral summit, which is the first of its kind, has taken place after a September agreement between Ankara and Moscow that stipulated the creation of a demilitarized buffer zone in Syria's Idlib province, the last major rebel-held territory in the country.