Turkish President Recep Tayyip Erdoğan is due to head to Sochi on Wednesday for a meeting on the Syrian conflict with his Russian and Iranian counterparts.
He is set to depart from Istanbul's Ataturk Airport at 12.30 p.m. local time (0930GMT).
Erdoğan, Vladimir Putin and Hassan Rouhani will meet to discuss progress made in the Astana peace talks as well as the changes in de-escalation zones across the country.
The leaders, who are meeting at the Rus Sanatorium, will also talk about tackling terror groups in Syria and delivering humanitarian aid.
The progress of the UN-backed Geneva peace process, which is seeking a political solution in Syria, will also be under discussion.
Erdoğan will have a separate meeting with Rouhani on the sidelines of the summit before Putin hosts Erdoğan and Rouhani at a dinner.
Turkey and Russia, together with Iran, are the guarantor countries which brokered a cease-fire in Syria in December 2016, leading to the Astana talks, which are running parallel to the Geneva talks.
