ISTANBUL (AP) — The leaders of Turkey, Russia, France and Germany are holding a summit in Istanbul to discuss security and humanitarian and political issues in Syria, hoping to lay the groundwork for eventual peace in a country devastated by years of war.

The leaders meeting Saturday afternoon 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.

Other discussion topics include access for humanitarian aid, early preparations for the drafting of a constitution and eventual reconstruction of the war-torn country.

Turkish President Recep Tayyip Erdogan is hosting Russian President Vladimir Putin, German Chancellor Angela Merkel and French President Emmanuel Macron.