Brussels, Belgium (BBN)-Ministers from EU and Balkan nations are meeting in Brussels to try to heal divisions over a migrant crisis that could threaten the bloc's survival.
Austria, Serbia and Macedonia have taken steps to restrict entry to migrants, angering Greece, which fears the controls will cause a bottleneck, reports BBC.
The rift places further strain on a common EU migration policy, already in disarray over the surge in migration.
More than 100,000 migrants have reached Europe this year, most via the Balkans.
European Council president Donald Tusk has warned that the failure to make progress towards resolving the crisis could increase the likelihood of the UK voting to leave the EU this year.
The EU interior ministers meeting in Brussels will hear plans drawn up by Austria and eight Balkan countries that seek to restrict the numbers entering their borders.
The measures include fingerprinting all entrants and turning back anyone without a passport or holding fake documents.
The countries have also pledged to accept only those they deem to be in need of protection, which has already been interpreted by some governments as meaning only Syrians and Iraqis.
Macedonia enacted the measures at its border with Greece over the weekend, barring entry to Afghans, who make up many of the migrants.
Austrian Interior Minister Johanna Mikl-Leitner described the measures as a "chain reaction of reason" and warned that the crisis could threaten the EU's survival if it was not brought under control.
But the plans drew sharp criticism from Greece, which threatened to block all decisions at an upcoming EU migration summit if member states did not agree to take in quotas of migrants.
Greek Prime Minister Alexis Tsipras said his country was turning into a "permanent warehouse of souls" and should not be left to deal with the crisis alone.
"From now on, Greece will not agree to deals if we do not secure the mandatory sharing of the burden and responsibility proportionally among member states," Tsipras said.
The UN refugee agency, UNHCR, has also criticised the measures. "The response is not closures, it is co-operation," said the agency's head, Filippo Grandi. "Everybody has to take a share of this burden."
An official from the current Dutch presidency of the EU told the AFP news agency that the purpose of Thursday's meetings would be "to allow us to avoid surprises - we have to avoid that one country is surprised by the measures taken by another."
IN SEPARATE DEVELOPMENTS:
Ships from a Nato mission fighting human-trafficking in the Aegean Sea will work with Turkish and Greek coastguards, according to a new agreement, overcoming territorial tensions between the two neighbours
A French judge is to decide whether to implement or postpone an eviction order for up to 1,000 migrants under plans to demolish part of the Calais "Jungle" camp
Belgium has detained 80 migrants on the French border since imposing controls on Monday evening, officials say. Many of the migrants are thought to have come from Calais
Germany expects to accommodate 3.6m migrants by 2020, German media reported, quoting internal government estimates
A special flight from Germany carrying 125 deported Afghans has arrived in Kabul, as Germany takes steps to reduce the number of people seeking asylum
Last September, EU ministers agreed plans to relocate 120,000 migrants from Italy, Greece and Hungary to other EU countries.
But the majority vote decision was opposed by Romania, the Czech Republic, Slovakia and Hungary.
On Wednesday Hungary announced it would hold a referendum on accepting mandatory EU migrant quotas.
Hungarian Prime Minister Viktor Orban stressed that the quotas "could redraw Europe's cultural and religious identity".
The referendum is expected to be held in the autumn, subject to parliamentary approval.
More than 100,000 migrants have arrived in Greece and Italy so far this year, the International Organization for Migration (IOM) said.
More than 400 migrants died attempting to make the journey during the same period, the IOM said.
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