Refugees travelling through the Balkans risk freezing to death as winter begins, the president of the European Commission has warned.
Jean-Claude Juncker said leaders need to find a solution to the crisis soon, as thousands of families continue to make the journey through eastern Europe.
"Every day counts," he said in an interview in German weekly newspaper Bild am Sonntag.
"Otherwise we will soon see families in cold rivers in the Balkans perish miserably."
At a meeting of EU and Balkan leaders in Brussels on Sunday, it was agreed that external borders agency Frontex would be called in to the Croatia-Serbia border to slow down the flow of people.
The measure was part of a 17-point plan agreed to help manage the flow of people through the Balkan peninsula.