Syrian leader Bashar al-Assad accused Turkey's President Recep Tayyip Erdogan of being the main instigator in the deadliest fighting between Armenian and Azeri forces for more than 25 years.
Turkey has denied involvement in the fighting in and around Nagorno-Karabakh, a mountain enclave that belongs to Azerbaijan under international law but is governed by ethnic Armenians, and has dismissed accusations that it sent mercenaries to the area.
But Assad told Russian news agency RIA: "He (Erdogan) ... was the main instigator and the initiator of the recent conflict in Nagorno-Karabakh between Azerbaijan and Armenia."
Reiterating accusations first levelled by French President Emmanuel Macron that Turkey has sent Syrian militants to fight in the conflict, Assad said: "Damascus can confirm this."
Turkish Foreign Minister Mevlut Cavusoglu said during a visit to Azerbaijan's capital, Baku, on Tuesday that international peace efforts had achieved no concrete results in decades and a ceasefire alone would not end the fighting.
"The whole world now needs to understand this cannot go on like this," Cavusoglu said.