The European Commission was not informed by Austria of plans to build a border with Slovenia, a EU spokesman has said, following Austria's announcement that it is considering building "fixed constructions" on certain crossings with Slovenia.
The development has sparked alarm in Brussels that the EU's borderless Schengen area could be under threat, as both Austria and Slovenia are part of the free travel zone. European Commission president Jean-Claude Juncker is due to speak by phone to Austrian chancellor Werner Faymann on Wednesday.
Interior minister Johanna Mikl-Leitner told Austrian radio on Wednesday morning that Austria needed to be prepared in case the flow of migrants and refugees worsens.
"Whether we want it or not, people are marching toward Germany, " she said.
Meanwhile, in the strongest intervention yet by a German politician, German interior minister Thomas de Maizière told a news conference in Berlin that Austria’s handling of the migration crisis was “out of order”. He accused Austrian authorities of driving refugees to the German border under darkness and leaving them there.
“The behaviour of Austria in recent days was out of order,” he said.
Waving on
The refugee crisis has sparked tensions between EU member states, amid fears that some countries are waving on refugees to neighbouring countries without ensuring they are properly registered. Bottlenecks have built up at key points such as the Slovenia- Croatia and Slovenian-Austrian border.
Speaking in Strasbourg on Tuesday, Mr Juncker said Europe needed to slow down "the uncontrolled flow of people".
"This means registering people when they enter the European Union. This also means informing refugees about the existing routes and the consequences of a refusal to be registered. I have to say: no registration, no rights. It is as simple as that."
On Tuesday, European Council president Donald Tusk warned that 100,000 refugees have already fled the Aleppo region of Syria since Russia's intervention in the war in September.
Despite expectations that the deteriorating weather conditions would deter refugees from embarking on the perilous journey from Syria to Europe, the International Organisation for Migration estimates that more than 9,000 migrants and refugees a day crossed into Greece last week, the most since the beginning of the year.