In a strong-worded warning late yesterday, Erdogan accused the Kurds of ethnically cleaning other communities from land they have taken after pushing back Islamic State forces from the Turkish border.
"I say to the international community that whatever price must be paid, we will never allow the establishment of a new state on our southern frontier in the north of Syria," Erdogan was quoted by Turkish media as telling guests at a dinner to break the Ramadan fast.
Turkey has fought a 31-year insurgency in the south east of the country by the Kurdistan Workers' Party (PKK), which Ankara claims is closely linked to the main Syrian Kurdish People's Protection Units (YPG) militia.
Erdogan's comments came a day after IS militants mounted a bloody surprise attack on the Kurdish-held border town of Kobane, killing at least 164.
More From This Section
Erdogan again denied persistent claims of Turkish collusion with the jihadists, saying, "It is a big lie to accuse Turkey of having link with a terrorist organisation."
Turkey is one of the fiercest opponents of Bashar al-Assad's regime in Damascus and has taken in more than 1.8 million refugees since the war in Syria began.
But in an interview with the Turkish newspaper Hurriyet, Saleh Muslim, the head of the Democratic Union Party (PYD) -- the political wing of the YPG militia -- denied they were trying to create an independent state. "We do not have such a project," he said.
The press claimed that the military high command demanded a written order from the government, with a new one yet to formed after the Justice and Development Party (AKP) lost its overall majority for the first time in 13 years in a parliamentary election on June 7.
Hurriyet also claimed that at least 12,000 Turkish troops were ready to enter Syria to create a "security zone" to protect the border from the threat posed by IS.