Turkey considers the PKK/PYD to be the Syrian offshoot of the PKK, a designated terrorist organization in Turkey, the U.S. and EU. However, the U.S. views the PKK/PYD as its ally in the fight against Daesh in northern Syria.
Ankara has also pressed Washington to hand over Gulen, who lives in exile and who Turkey blames for the deadly coup attempt last July.
Prior to his sit-down with the Turkish president, Tillerson met Foreign Minister Mevlut Cavusoglu ahead of a major oil conference in the same city.
The two diplomats discussed the war in Syria, the fight against terrorism as well as the Qatar crisis during a working dinner at the Prime Ministry Office, according to diplomatic sources.
Earlier in the day Tillerson received the highest recognition of the World Petroleum Council, the largest meeting of the oil and gas industry, that began its conference Sunday at the Istanbul Convention Center (ICC).
The Congress, in which Anadolu Agency is the global communication partner, will run its conference through July 13.
The American diplomat acknowledged the victims of last year's deadly coup attempt while receiving his award.
"Nearly a year ago, the Turkish people, brave men and women, stood up against coup plotters and defended their democracy," Tillerson said.
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