Balkan countries at the front line of the migrant crisis say they could close their borders to avoid becoming buffer zones for new arrivals.
Bulgaria said it, Romania and Serbia would act if states further north, which migrants hope to reach, close their doors, BBC reported.
The threat comes ahead of talks between Balkan states and EU members.
Slovenia’s president said his country would “act on its own before it is too late” if no solution was reached.
Prime Minister Miro Cerar had previously refused to rule out building a fence along its border with Croatia.
Bottlenecks have also been exacerbated in part by Hungary closing its borders with Serbia and Croatia, forcing migrants to seek alternative routes north.
Slovenia saw 58,000 arrivals in the week leading up to Saturday and many people are waiting in wet and cold conditions.
While Germany has not indicated it would refuse more migrants, Bulgaria’s prime minister said on Saturday that his country, Romania and Serbia would respond immediately if it did so.
“We are standing ready, if Germany and Austria close their borders, not to allow our countries to become buffer zones,” Prime Minister Boiko Borisov said. “We will be ready to close borders.”
Slovenia’s President Borut Pahor echoed Borisov’s concerns, saying it “cannot become a pocket in which refugees would be stuck” if Germany and Austria refused to take migrants.
On his Facebook page, Pahor said the success of Sunday’s summit would be measured partly on whether stricter controls are implemented to stop migrants traveling from Turkey to Greece.
Croatian Prime Minister Zoran Milanovic said such controls were the only solution. “Everything else is a waste of time,” he said.
The leaders of all affected countries will attend the emergency summit in Brussels.
German media say countries will be presented with a 16-point plan by European Commission President Jean-Claude Juncker.
