As Moscow prepares for its Syrian National Dialogue Congress this month, the guest list might still be in flux. Russia hopes to broker peace between the Syrian regime and its opposition while appeasing major stakeholders — who at the moment aren't playing nicely.

On Jan. 11, Turkish President Recep Tayyip Erdogan called Russian President Vladimir Putin to discuss the Syrian situation. This was two days after Turkey had summoned the Russian and Iranian ambassadors over cease-fire violations in the Idlib de-escalation zone. Under the preliminary peace agreements reached in Astana, Kazakhstan, the three guarantor countries for the four Syrian de-escalation zones are Turkey, Russia and Iran.

Ankara couldn’t be more displeased with the recent offensive in Idlib by Syrian government forces with the support of pro-Iranian militias and Russian air power. Al-Monitor correspondent Amberin Zaman reported Jan. 10 that Turkish Foreign Minister Mevlut Cavusoglu criticized Moscow and Tehran for failing to stop the offensive.

But Moscow had its own grievances with Ankara, whose peace-monitoring forces entered Idlib in October and chose to “coexist rather than curb" the actions of al-Qaeda-linked group Hayat Tahrir al-Sham.