Defense Minister Hulusi Akar told the U.S. delegation at the Munich Security Summit that the PKK's Syrian offshoot People's Protection Units (YPG) remains to be the biggest obstacle on the relations between Turkey and the U.S.

Akar had a meeting with acting U.S. Secretary of Defense Patrick Shanahan, U.S. Special Representative for Syria Engagement James Jeffrey and 12 senators.

Noting that the YPG terrorists do not represent Kurdish people, Akar said that it is necessary to clear the terrorists east of the Euphrates River.

"A 440-kilometers long (273-mile) safe zone in the east of Euphrates should be cleared of the YPG terrorists and should be patrolled by the Turkish forces," Akar said.

In its more than 30-year terror campaign against Turkey, the PKK -- listed as a terrorist organization by Turkey, the U.S. and the EU -- has been responsible for the death of some 40,000 people, including many women and children.

In December, U.S. President Donald Trump announced that the U.S. would withdraw its troops from Syria, saying that Daesh was defeated. Days after, President Recep Tayyip Erdoğan pledged that Turkey will take over the fight against the remnants of Daesh in Syria but put the likely operation east of the Euphrates against the YPG on hold.

However, Ankara and Washington have been at odds for some time now due to the latter's close partnership with the YPG. Turkey sees the YPG as an extension of the PKK, which has claimed the lives of more than 40,000 people its 30-year terror campaign against Turkey. The U.S., however, while listing the PKK as a terrorist group, opted to continue its steadfast militarily support for the terrorist organization under the pretext of fighting Daesh despite the warnings of its NATO ally.