The European Commission is "very concerned" about Austrian plans to introduce strict border controls on a key mountain pass to Italy in the case of a migration surge from its southern neighbour, a spokeswoman said Tuesday.
Austria and Italy are both members of the European Union's free-border Schengen area, which has been severely tested by an influx of more than 1 million migrants and asylum seekers to Europe last year.
The EU has implemented a series of measures in recent months, aimed at ending the go-it-alone approach of countries along the migration route from Greece to Europe's wealthy north, many of whom have effectively shut their borders to new arrivals.
Austria plans to ratchet up controls along its entire southern frontier in case of rising migrant numbers in the coming months, including the Brenner mountain pass, which lies on one of Europe's busiest transport routes.
A police spokesman in Tyrol province said Tuesday that preparations had started at the Brenner.
Workers were building a roof over the section of road where vehicles will be stopped and searched, the spokesman told dpa, adding there is no starting date for building a fence.
As long as border protection at the EU's external frontiers is not secured, it is "politically necessary and right for Austria to take the right steps," Austrian Chancellor Werner Faymann said, hinting at early June as the starting date for controls at the Brenner.
"The commission is very concerned," European Commission spokeswoman Natasha Bertaud said. "If these plans should materialize then we will have to look at them very seriously. The Brenner pass is essential for the freedom of movement within the EU."
The EU's executive will assess the "necessity and the proportionality" of any measures taken by Vienna, Bertaud added, noting that EU Migration Commissioner Dimitris Avramopoulos was due to talk to Austria's outgoing interior minister, Johanna Mikl-Leitner, later in the day.
Bertaud said there is currently "no evidence" that migration flows are shifting from Greece to Italy since the implementation of a deal struck between Turkey and the EU aimed at stemming new arrivals. Last year, most people crossed by sea from Turkey to the Greek islands.
But she said there has been an increase in the numbers of people reaching Italy, with more than 15,000 people arriving by sea from Libya since the beginning of March, when the EU-Turkey deal was finalized.
Socialist EU lawmaker Gianni Pitella, an Italian national, said it was "unacceptable" for Austria to erect a barrier on the Brenner pass, adding that a "new level of absurdity" had been reached.
"It again demonstrates that national governments prefer to lock themselves in national fortresses rather than look for a comprehensive and effective European solution," he said.