The Turkish Foreign Ministry separately summoned Russian and Iranian ambassadors in Ankara on Tuesday and warned its partners for violation of Astana deal in a bid to stop the regime's attack on "moderate opposition" forces in northern province of Idlib, where "de-escalation zone" was declared by three guarantor powers.
"Iran and Russian Federation need to carry out their responsibilities".
The Turkish foreign minister noted that Damascus could not have made big military advances without the active support of Russian Federation and Iran.
"Russia and Iran must stop the Syrian regime".
Ankara and Moscow have many times not been seeing eye to eye on Syrian conflict since they have different interests in the region.
Turkey and the United States have been at loggerheads over Washington's policy of support for the YPG, which Ankara views as an extension of the Kurdistan Workers Party (PKK) that has waged an insurgency in Turkey's largely Kurdish southeast for more than three decades.
A previous attempt in November to convene talks in Sochi failed due to disagreements between the prospective participants.
The People's Protection Units (YPG), the armed wing of the Syrian Kurdish Democratic Union Party, or PYD, is seen by the U.S. as the most effective ground partner for the US-led coalition fighting ISIL in Syria. Turkish Foreign Minister Mevlut Cavusoglu warned Moscow and Tehran that they must fulfill their duties under the de-escalation zone accord struck with Ankara past year. The Russian embassy in Ankara did not issue any comments.
The YPG is supported by USA with arms and training which angers Turkey.
Idlib province is nearly entirely controlled by anti-government forces that are dominated by a jihadist outfit known as Hayat Tahrir al-Sham (HTS) consisting mostly of former fighters from the Al-Nusra Front, an Al Qaeda affiliate.