"The migration deal between the EU and Turkey failed. Germany should have never supported it. It was a big mistake," Georg Pazderski said.
Pazderski added that the submissive strategy of German Chancellor Angela Merkel regarding relations with Turkey, particularly with Turkish President Recep Tayyip Erdogan, and the migration issue "obviously failed."
"She should skip the deal and secure the German borders, to prevent further mass immigration to Germany," the chairman added.
In March, Brussels and Ankara agreed on a deal under which Turkey pledged to take back all undocumented migrants who arrive in the European Union through its territory in exchange for Syrian refugees accommodated in Turkey. In return, the bloc pledged to accelerate the Turkish EU accession bid and introduce a visa-free regime.
Turkey is yet to meet five out of the 72 total requirements, notably those related to data protection and anti-terrorism laws, among other issues.
On Tuesday, Erdogan said Turkey might suspend the migration deal, if the bloc fails to proceed with the visa-free regime. On Wednesday, Merkel responded by saying that the European Union will resolve the situation if the visa process for Turkey took more time than expected.