In Germany: Minister concerned migrant numbers via Libya, Italy will rise

"What we have demonstrated is that the rule of law, the essential measure for us is that we want to register people who come to Austria, that our borders are not overrun," Sobotka said.

  Migrants receive emergency relief in a port, after being rescued at sea by Libyan coast guard, in Tripoli, Libya April 11, 2016. 

Migrants should no longer be able to get to Germany and Europe via the Balkan route, German Interior Minister Thomas de Maiziere said on Friday, adding he was concerned refugee numbers would rise with people now coming to Italy by sea from Libya.

"It's clear that the Balkan route is a thing of the past and no longer will or should be a place again from where people will be waved through to Germany and Austria and to the centre of Europe," he said at a joint news conference with Austrian Interior Minister Wolfgang Sobotka in Potsdam near Berlin.

"Now the issue is alternative routes ... we are of course concerned that we'll get rising refugee numbers again as they come via Libya and Italy," he added.

De Maiziere said he agreed with Austria that the situation at Italy's northern border should not replicate the situation on the Balkan route last year.

Austria has said it might reintroduce border controls at the Alpine Brenner pass to keep migrants from coming from Italy and Italian Prime Minister Matteo Renzi has said Austria's plans to build a fence there were "shamelessly against European rules".

Sobotka said the measure was necessary to prevent the route from turning into a major corridor for migrants seeking to reach northern Europe after they arrive to Italy through the Mediterranean from Libya and other north Africa nations.

"What we have demonstrated is that the rule of law, the essential measure for us is that we want to register people who come to Austria, that our borders are not overrun," Sobotka said.

He added: "This border management that has been in place since February is effective and we have applied this on the border with Hungary ... and we are preparing for this on the border with Italy."

De Maiziere and Sobotka both piled pressure on Italy to take responsibility.

"What is happening at the Brenner border crossing lies first and foremost in the hands of Italy," de Maiziere, said, adding that on the issue of border controls, states were working together but still needed a few more days to reach a European solution.