A senior figure in Chancellor Angela Merkel's conservative party has proposed setting up "border centres" along Germany's frontier with Austria to speed up the repatriation of asylum seekers unqualified to stay.
Julia Kloeckner, leader of Merkel's Christian Democrats in the western state of Rhineland-Palatinate, was careful to style her proposal as a "Plan A2" rather than a "Plan B", adding that the chancellor's push for a European solution to a large influx of asylum seekers into the continent was still right.
"We want to complement it," she wrote in a paper setting out her position.
In the paper Kloeckner proposes that: "On the German-Austrian border, border centres will be set up."
The proposal, endorsed by the Christian Democrats' secretary general, highlights the frustration in Merkel's party with the slow progress in achieving a European Union-wide solution to the refugee crisis, which is straining the infrastructure of many German municipalities.
Germany attracted 1.1 million asylum seekers last year, leading to calls from across the political spectrum for a change in its handling of the number of refugees coming to Europe to escape war and poverty in Syria, Afghanistan and elsewhere.
Growing concern about Germany's ability to cope with the influx and worries about crime and security after assaults on women at New Year in Cologne are weighing on support for the CDU and its Bavarian sister party, the Christian Social Union.
Merkel, despite appearing increasingly isolated over her open-door policy on refugees, has resisted pressure from some conservatives to cap the influx, or to close Germany's borders.
Instead, she has tried to convince other European countries to take in quotas of refugees, pushed for reception centres to be built on Europe's external borders, and led an EU campaign to convince Turkey to keep refugees from entering the bloc. But progress has been slow.