LJUBLJANA (Slovenia) • The European Union will hold a mini-summit with Balkan countries on the migrant crisis, as small Slovenia became the latest bloc member to buckle under a surge of refugees desperate to reach northern Europe ahead of winter.

The leaders of Austria, Bulgaria, Croatia, Germany, Greece, Hungary, Romania and Slovenia will meet counterparts from non-EU states Macedonia and Serbia on Sunday, the office of European Commission President Jean-Claude Juncker said.

"In view of the unfolding emergency in the countries along the western Balkan migratory route, there is a need for much greater cooperation, more extensive consultation and immediate operational action," a statement said.

The continent has been struggling to find a unified response on how to tackle its biggest refugee crisis since 1945.

More than 600,000 migrants and refugees, mainly fleeing violence in Syria, Iraq and Afghanistan, have braved the dangerous journey to Europe so far this year, the United Nations said.

The goal for many travelling along the western Balkan route is the EU's biggest economy Germany, which expects to take in up to one million refugees this year.

Since last Saturday, when Hungary sealed off its border with Croatia, more than 21,455 migrants have arrived in Slovenia, a nation of two million people.

In response to the crisis, Prime Minister Miro Cerar on Tuesday asked the EU for backup from police in other EU countries and extra equipment for its own officers.

The Slovenian Parliament also amended the country's defence law yesterday to allow soldiers to join border police in patrolling the 670km frontier with Croatia.

Under the measures, soldiers can detain people and hand them over to police, as well as issue orders to civilians in the border area.

Between 8,000 and 9,000 people arrived in Slovenia on Tuesday, according to local media, after a long trek through Greece, Macedonia, Serbia and Croatia.

Meanwhile, reports said several hundred more migrants were waiting in cold weather near the Croatian border to cross into Slovenia yesterday.

With at least 9,000 people landing on Europe's beaches every day, there appears to be no end in sight to the continent's biggest migration wave since World War II.

EU member the Netherlands announced yesterday it had received a record 8,400 asylum-seekers in September, the highest number received in one month.

AGENCE FRANCE-PRESSE