Greece has recalled its ambassador to Austria amid sharp divisions among EU states over the migrant crisis.It came after Austria hosted a meeting with Balkan states on the migrant issue, to which Greece was not invited.
Meanwhile, EU and Balkan interior ministers have met in Brussels to try to heal rifts over the migrant issue.
Speaking afterwards, the EU's migration commissioner warned that the bloc's migration system could be days away from complete breakdown.
Dimitris Avramopoulos said member states had until a 7 March summit with Turkey to curb the number of migrants.
"In the next 10 days, we need tangible and clear results on the ground," he told reporters.
"Otherwise there is a risk that the whole system will completely break down."
Austria, Serbia and Macedonia have taken their own steps to limit entry to migrants, angering Greece, which fears the controls will cause a bottleneck. The measures also threaten Europe's Schengen passport-free travel area that spans 26 countries.
Note EU-Digest: Greece's migration minister has accused fellow EU countries of hypocrisy and lying about Greece's handling of the huge migrant influx from Turkey.
"We have the best control of a sea border that anyone can have," he added.
Read more: Migrant crisis: Greece recalls ambassador from Austria amid EU rifts - BBC News