Sinn warned of future distribution conflicts between refugees and Germans with modest economic prospects.

"The welfare state will inevitably be damaged by free migration," the prominent German economist Hans-Werner Sinn told the newspaper "Tagesspiegel."

This would also hurt the poorest citizens, he added. According to the Munich-based Ifo Institute, the integration of refugees will cost Germany 21 billion euros in 2016.

Ifo president Hans-Werner Sinn stated that the country should not take on debts for integrating migrants, but resort to the current budget. He stressed that this was possible, adding: "At the moment, we still have a surplus."

In his opinion, the priority should be to integrate the refugees into the German labor market. However, their level of qualification must not be overestimated, he added: "About half of the Syrian refugees living in Turkish camps do not have the most basic knowledge of arithmetic that is needed here."

In the "Tagesspiegel" interview, Hans-Werner Sinn rejected proposals to forgo the minimum wage in order to make it easier for refugees to find a job. It would have a negative impact on the local workforce if refugees accepted salaries that undercut the minimum wage, he stressed.

More than 1.1 million people came to Germany seeking asylum in 2015.

Horst Seehofer, the head of the Christian Social Union (CSU), the Bavarian sister party to Angela Merkel's Christian Democratic Union (CDU), told the newspaper "Bild am Sonntag" that Germany could take in "a maximum of 200,000 refugees" per year. His party is at odds with Merkel's persistence that the country must keep its borders open to a massive influx of refugees.

das/rc (dpa, KNA, epd)