Germany will ask the European Commission to allow an extension of temporary border controls within the Schengen zone of passport-free travel beyond mid-May, Interior Minister Thomas De Maiziere said on Saturday.
Germany and some other European Union members have introduced temporary border checks to control or halt record flows of migrants fleeing conflicts in Syria, Iraq and elsewhere and traveling to western Europe via the Balkans.
Germany took in more than one million migrants last year. But the number of arrivals has slowed significantly after border clampdowns were imposed by Austria and other countries along the migrants' main Balkans route northwards from Greece.
"Even if the refugee situation has eased at internal borders along the West Balkan route, we look with concern at the developments on the external borders of the Union," De Maiziere said in a statement.
Berlin will therefore ask the European Commission, the EU's executive arm, to allow the border controls to be extended beyond May 12 when the legal basis for the current measures expires, he said.
A German government official said the request was a joint initiative by Germany, France, Austria, Belgium, Denmark and Sweden and the letter would be sent to Brussels on Monday.
"Member states must continue to have the flexibility and option to conduct border controls at their internal borders in cases when it is necessary," De Maiziere said, adding such measures were required to guarantee a certain level of safety.
A European Commission source told Reuters that Brussels was leaning towards giving its green light to the request and to allow an extension of the border checks until November.
The numbers of migrant arrivals to Germany has dropped to less than 200 daily in recent weeks from more than 2,000 daily in January. At the height of the refugee crisis last autumn, more than 10,000 migrants arrived in Germany on some days.
In her weekly podcast, German Chancellor Angela Merkel urged EU member states to avoid seeking national solutions to European problems, adding that she would fight to uphold EU citizens' right to freedom of movement and residence within the bloc.
Merkel has been critical of border closures within the EU and is instead banking on an EU-Turkey deal that took effect early April and gives Ankara political and financial benefits in return for taking back refugees and migrants who have crossed to Greece en route for Germany and other west European states.