Turkish Prime Minister Binali Yildirim also said Tuesday the Antalya meeting is aiming at coordination among militaries of the three countries in Syria.
The surprise meeting between Turkey's Gen. Hulusi Akar, Marine Corps Gen. Joseph Dunford, the chairman of the U.S. Joint Chiefs of Staff, and Gen. Valery Gerasimov, the chief of the Russian General Staff, took place in the Turkish coastal city of Antalya.
Turkey's inclusion in the meeting comes as its military moves farther south into Syria from Turkish territory.
United States troops were first spotted in Manbij on Saturday, following reports of a deal between the US-backed Syrian Democratic Forces (SDF) and the Syrian government to hand over some 20 villages in a zone between Manbij and Al-Bab, recently taken by Turkish-backed forces.
War Crime, UN Says: Suspected Chemical Attack Sickens 12 Civilians in Mosul
Iraqi forces launched attacks against ISIS-held neighborhoods in western Mosul from three points on Sunday morning. Four of them are showing "severe signs associated with exposure to a blister agent".
The U.S. military hopes to use the SDF, bolstered with recruits, to capture the city of Raqqa, the Islamic State's Syrian capital, in an offensive planned for this year.
The U.S. and Russian Federation blocked an attempt this week by Turkey and its Syrian rebel allies to take positions from Kurdish forces that have recently allied with the Syrian army in northern Syria, resulting in a major shift in momentum among the three nations sponsoring separate actors in the country's six-year civil war.
The statement did not say when the meeting was held.
Russian Federation launched an operation against militants of the Islamic State group (outlawed in Russia) in September 2015.
UN Syria envoy says talks have set agenda for progress on peace
However, after a week of indirect talks, little progress has been made in getting the two sides to the negotiating table. The geopolitical circumstances in which this year's round of peace talks are set also transcend Syrian borders.
Turkey, however, has labeled Kurdish militants such as those belonging to the People's Protection Units within the SDF as terrorists and has refused to recognize their position in the larger fight against ISIS.
It came after Russian and Syrian regime forces started to move "humanitarian" convoys into Manbij, making it more hard for Turkish troops to launch the offensive they had threatened.
The military summit in Antalya was the second meeting of the Russian and US military chiefs in less than a month.
Turkey views the YPG as an extension of the Kurdistan Workers Party (PKK), which is waging an insurgency in Turkey. The ceasefire in Syria came into force on December 30, 2016. Some Russian and Syrian regime aircraft mistakenly bombed a village that Syrian Arab Coalition forces had liberated from ISIS.
Lab tests found less than 1% soy protein in Subway chicken
Other major Canadian fast food chains, however, do not resort to such drastic restructuring as Subway. Subway has shared the results of the independent tests with CBC and the lab that conducted the test.