President Recep Tayyip Erdogan warned that the attack, which the defense minister claimed had "neutralized" 254 terrorists, was "only the beginning".
Turkey blames Kurdish groups for recent deadly Istanbul bombings.
The YPG denied involvement and said 30 civilians and 11 militants were killed in attacks in northeastern Syria.
The Pentagon said the Turkish strike "directly threatened the security of U.S. personnel" working to defeat the Islamic State (IS) group in Syria.
The YPG-controlled US-backed militia alliance, the Syrian Democratic Forces (SDF), has accused Turkey of using the Istanbul bombing as a pretext for a long-planned cross-border attack. . Turkish forces have launched three major operations with allied Syrian rebel groups in northern Syria since 2016 and now control territory stretching more than 200 miles (325 km) from the border.
In its latest operation in 2019, Turkey occupied an area between the towns of Tal Abyad and Ras al-Ain before Russia negotiated a ceasefire.
Turkey views the YPG as a terrorist group, claiming it is an offshoot of the Kurdish Workers' Party (PKK) that has fought for Kurdish autonomy in Turkey for decades. The PKK has also denied involvement in the Nov. 13 Istanbul bombing that killed six of his people in central Istiklal Street.
Speaking with his AKP members in parliament on Thursday, Erdogan said Turkey's determination to secure its border with Syria and set up a "security corridor" was "stronger than ever." "We will continue our air operations and violently attack terrorists from the ground when it is most convenient for us," he warned.
Self-Defense Forces Commander Mazuruum Abdi told Al-Monitor that he believed his hometown of Kobane would be a "real target" for a ground attack, adding that an attack in Istanbul would be "a threat to Syrian rebel groups operating under Turkish control." It was carried out by
Abdi also said Russia and the US are not enough to deter Turkey.
Russia, an ally of the Syrian government, has warned Turkey that an all-out ground attack could spark an escalation of violence.
"I hope our discussions will be heard in Ankara and other ways of resolving the issue will be found," said Russian negotiator Alexander Lavrentyev after the meeting in Kazakhstan.
Turkey's NATO ally, the United States, has warned of the impact of escalation on its goals of fighting IS. The US relied on the YPG and other SDF militias to defeat ISIS in eastern Syria.
Japan's Self-Defense Forces said on Wednesday it had carried out five Turkish airstrikes targeting Kurdish security forces guarding the al-Hol detention center, where relatives of suspected Islamic State militants are being held.