Turkey has repeatedly threatened to hit targets in Manbij to prevent the expansion of the YPG's influence in northern Syria
The Turkish military said on Friday 71 Kurdish fighters from the Syrian Kurdish YPG militia and the allied Kurdistan Workers Party (PKK) had been killed in operations in Syria over the past week.
Turkey launched an operation to drive Islamic State (IS) away from its border with Syria in August, and has said that it would strike the US-backed YPG if necessary to prevent them seizing territory there.
Turkey has long demanded that the YPG move out of the Syrian town of Manbij, which it seized last year from IS after a months-long offensive as part of the Syrian Democratic Forces, to the eastern side of the Euphrates river. Ankara sees the fighters as a terrorist group allied to the PKK, which has waged a three-decades-old insurgency in southeast Turkey.
Speaking in Ankara on Tuesday, Turkish Prime Minister Binali Yildirim said Syria needed to be rid of "all terrorist groups" including Al-Nusra, Syrian Kurdish militia as well as IS.
"The objective of the meetings today and tomorrow is how to provide coordination in the best way possible and prevent parties from interfering with each other's operations and cause unpleasant developments while fighting against terror," Yildirim said, referring to a trilateral meeting with US and Russian military officials that took place on Wednesday.
"Naturally terror elements are a common threat and spoil peace and (the possibility of) political solution in Syria."
The comments came a day after Turkey stepped back from threats to unilaterally strike Kurdish militia deployed in Manbij.
"It makes no sense to launch an operation in Manbij without the cooperation of Russia and the United States," Yildirim said in a televised interview late on Monday.
His announcement stood in stark contrast to previous threats from Ankara that it would hit Syrian Kurdish militia unless they withdrew from Manbij.
However on Tuesday Yildirim criticised some allies' "unfortunate" choice of Kurdish militia linked to separatist rebels in Turkey as partners against terror groups.
The Pentagon said it has sent extra troops into northern Syria to make sure competing forces in and around Manbij remain focused on fighting IS rather than each other.