Meanwhile, Serbia's Interior Ministry said that Slovenia will demand valid EU visas at its borders as of midnight Tuesday, effectively closing the main Balkan migration route toward Western Europe, the Associated Press reported.
The ministry said that Serbia will coordinate its moves with the EU and close its borders with Macedonia and Bulgaria for refugees and other migrants who don't have valid visas.
The decision will prevent thousands of migrants currently stranded in Greece on the border with Macedonia from proceeding north toward Serbia, Croatia, Slovenia and Austria.
Turkey and the European Union clinched a landmark deal on Tuesday on a proposal to tackle the massive influx of refugees into Europe.
Ankara reaffirmed an agreement with Greece to take back migrants attempting to reach the European Union — a key condition set by EU leaders ahead of the meeting.
The six-point agreement will put an end to the illegal flow of migrants from the Near and Middle East into the European Union via the Balkans and will help restore visa-free travel within the 28-nation bloc.
According to the latest Frontex data, about 1.8 million refugees entered the European Union in 2015.