The leaders of Germany and France are meeting Greek Prime Minister Alexis Tsipras amid growing worry about Greece's lack of control over thousands of migrants crossing its borders into the European Union every week.

Tsipras, Chancellor Angela Merkel and France's Francois Hollande are talking on the sidelines of a European Union summit in Brussels on Friday. Six hours of talks the night before highlighted still-deep divisions across the continent about how to deal with the EU's worst-ever refugee crisis.

Officials said leaders at Thursday's talks argued over conflicting national reactions to the migrant influx, and the potential collapse of Europe's border-free travel.

The EU's executive Commission has given Greece three months to restore order on its borders, but few believe Athens will be able to meet the deadline.