ISTANBUL, Aug. 29 (Xinhua) -- Turkish Deputy Prime Minister Numan Kurtulmus on Monday once again called on the United States to keep its promise by forcing the Syrian Kurdish militias to return to the east of the Euphrates River.
The refusal to retreat by the Democratic Union Party (PYD) forces have reportedly sparked shellings on them by the Turkish military in the past days.
"The U.S. knows Turkey's sensitivity on this issue," Kurtulmus told the press in Istanbul. "A promise was given; the PYD won't be positioned in the west of the Euphrates."
Earlier in the day, Brett McGurk, the U.S. president's special representative, criticized the clashes that broke out in northern Syria between Turkish forces and the People's Protection Units, the PYD's military wing.
Ankara has long insisted on the withdrawal of the PYD forces to the eastern side of Euphrates, fearful that they would manage to establish a Kurdish state in Syria's north.
Last Wednesday, the Turkish army crossed into northern Syria and drove Islamic States militants out of the Syrian border town of Jarablus.
The other objective of the operation was believed to roll back recent advances by Syrian Kurdish forces in the region.
Washington has urged Syrian Kurds to comply with Ankara's demand, warning they risk losing U.S. support if failing to do so.
Turkey considers the Syrian Kurdish groups as a branch of the outlawed Kurdistan Workers' Party (PKK), which has been seeking autonomy in southeastern Turkey over the past decades.
The PKK is listed as a terrorist organization by the United States, the European Union and Turkey.
