Turkish President Recep Tayyip Erdogan (C), Russian President Vladimir Putin (R) and Iranian President Hassan Rouhani attend a joint press conference after their meeting in Ankara, Turkey, on April 4, 2018. The leaders of Russia, Turkey and Iran on Wednesday called for a "lasting ceasefire" in Syria and expressed their commitment to the territorial integrity of the war-torn country during a trilateral summit in Ankara. (Xinhua/Mustafa Kaya)