The unprecedented influx of refugees and migrants flooding into the European Union could be the bloc's greatest-ever challenge, Germany's foreign minister said Friday at Prague crisis talks with eastern EU members refusing migrant quotas.

Europe's largest refugee crisis since the end of World War II could be "the biggest challenge for the EU in its history," said Frank-Walter Steinmeier, calling for solidarity as Berlin "expects 40,000 new migrants from the south at the weekend."