"Manbij is a place 85-90 percent populated by Arabs, but they (the U.S.) have completely given it to a terrorist organization. They said we're going to eject them. They did not. If you don't, we will enter Manbij," Erdoğan said, speaking at a judiciary conference of the Organization of Islamic Cooperation (OIC) in Istanbul.
The president also reiterated Turkey's determination to bring peace to the area east of the Euphrates River in Syria.
"Turkey has lost enough time in tackling the terrorist swamp in the east of the Euphrates. We cannot tolerate a single-day delay for this," he said.
Addressing the YPG attack, which left one Turkish soldier dead Thursday in Tel Rifaat, Erdoğan said it showed how right Turkey was to conduct Operation Olive Brach in Afrin.
"This [attack] shows that the terrorists and weapons piling on our borders will eventually target us," the president added, slamming the U.S. for the continuing supplying arms and training to the YPG terrorists.
Earlier this week, Erdoğan announced that Turkey will launch another anti-terrorist operation in northern Syria, targeting the area east of the Euphrates within a few days.
The United States' ongoing steadfast support to the YPG and the terrorist organization's subsequent increase in strength in the region have prompted Ankara to take necessary steps to ensure its national security.
Previously, Turkey targeted the PKK terror group's Syrian affiliate YPG in two cross-border operations, Operation Euphrates Shield launched in August 2016 and Operation Olive Branch in January 2018, as well as through air and artillery strikes.
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 deaths of some 40,000 people, including women and children.