Germany and five other European countries will ask EU authorities to allow border controls within the normally free-travel Schengen area to continue for another six months, German government sources said on Saturday.
One of Europe's most-cherished achievements, Schengen usually is the epitome of free movement, with 26 countries allowing free travel across their bloc without the need for passports or border checks.
But several Schengen nations have reintroduced internal border controls to stem migration flows, after the arrival of hundreds of thousands of migrants and asylum seekers overwhelmed their systems.
The uncontrolled flows were largely blamed on Greece, which has been accused of letting migrants pass through unchecked until countries further north shut down their borders.
Unannounced EU inspections in November found "serious deficiencies" in Greece, whose border with Turkey is an external Schengen frontier.
The EU has given Athens until May 12 to fix the problems. Its executive, the European Commission, has said that it is otherwise ready to propose that intra-Schengen border controls be allowed to continue for up to two years.
Commission spokeswoman Mina Andreeva said on Saturday that the Brussels institution has "its decision on this ready for next Wednesday" already.
Austria, Belgium, Denmark, France, Germany and Sweden will ask the commission to extend the border controls for another six months, the German newspaper Die Welt reported.
German government sources on Saturday confirmed the report, saying that a letter to Brussels is expected to be finalized on Monday.
This comes despite statements from German Interior Minister Thomas de Maiziere in early April which suggested that his country could end border controls on May 12.
Its controls at the Austrian border were introduced in September, when as many as 10,000 migrants were arriving in Germany each day. But border closures in other European countries have caused the influx to dwindle.
Domestic critics of German Chancellor Angela Merkel have pushed for unilateral measures to control the influx, such as tighter border controls and a cap on the number of arrivals.
But border controls have raised concerns within Europe because they hamper the free movement of people and goods and generate economic costs. They have also fuelled speculation that Schengen may eventually break apart.
Most recently, a plan by Austria to introduce border controls on a key mountain pass to Italy have strained relations between those two countries. Commission President Jean-Claude Juncker is expected to discuss the row with Italian Prime Minister Matteo Renzi on Thursday.