"The Turkish regime has been concealing and strengthening its military presence in Syria as a military power. These steps betray Turkey's hostile intentions regarding Syria, and all of it reflects on the security in the region," Sousan said at a press conference after the talks.
The official called the illegal presence of Turkey and the United States "the main factors hindering the restoration of stability across Syria's territory."
Damascus has voiced multiple complaints about the Turkish military presence and operations against Kurdish armed groups at the Syrian northern border, calling them illegal and demanding Ankara to withdraw its forces.
The Astana trio, which comprises Russia, Turkey and Iran, has been trying to bring the conflicting sides together to achieve a peaceful settlement in the Syrian conflict since their first meeting in the Kazakh capital of Astana (now Nur Sultan) in January 2017.