President Recep Tayyip Erdogan said his government had begun to allow refugees to travel on to Europe from Turkey, which he said can no longer handle new waves of people fleeing war-torn Syria.
"What did we do yesterday? We opened the doors," Erdogan told the Turkish Parliament on Saturday, in his first comments since 33 Turkish troops were killed in northern Syria on Thursday.
In 2016, Turkey signed a deal with the EU to stop refugees crossing from its borders after the 2015 migrant crisis that saw one million crossed the Aegean into Europe.
Erdogan also said 18,000 refugees had gathered on the Turkish borders with Europe since Friday, adding that the number could reach as many as 30,000 on Saturday.
Turkey, which is already home to the world's largest number of refugees - around 3.6 million Syrians, has repeatedly warned that is overburdened.
"We are not in a situation to handle a new wave of refugees" from Syria, Erdogan said.
Erdogan has previously threatened to "open the gates" unless more international support was provided, particularly at times of tension with European countries.