The leaders of Turkey, Russia, France, and Germany are holding a summit on October 27 in Istanbul to discuss security and political issues in Syria, hoping to find a lasting political solution to Syria's seven-year civil war, which has killed over 400,000 people and displaced millions more.
Turkish President Recep Tayyip Erdogan is hosting Russian President Vladimir Putin, German Chancellor Angela Merkel, and French President Emmanuel Macron.
"The eyes of the world are on us today... I hope we will act with a sincere and constructive understanding and will not fail to meet their expectations," Erdogan said as he opened the summit.
They are expected to promote the preservation of a cease-fire in Syria's northwestern province of Idlib.
The agreement last month prevented a Syrian government offensive on the last rebel stronghold that many feared would have set off another refugee crisis.
Topics such as access for humanitarian aid, early preparations for the drafting of a constitution, and eventual reconstruction of the war-torn country are expected to be discussed at the summit.
Turkish presidential spokesman Ibrahim Kalin said on October 26 that the primary goal would be to "clarify the steps to be taken for a political solution and to determine a road map."
Putin and Macron spoke by phone ahead of the summit in Istanbul, Kremlin spokesman Dmitry Peskov was quoted as saying by Interfax.
They discussed arranging a high-level Russia-U.S. meeting in Paris, Peskov was quoted as saying.
CNN Turk reported that Turkish Foreign Minister Mevlut Cavusoglu met his Russian counterpart, Sergei Lavrov, ahead of the four-way summit, without providing any details.