President Recep Tayyip Erdogan on Sunday likened German actions to stop the meetings of resident Turks with those of the Nazi period. The meetings were to be addressed by Turkish ministers.
"Germany, you have no relation whatsoever to democracy and you should know that your current actions are no different to those of the Nazi period," Erdogan said while addressing a rally in Istanbul.
German authorities withdrew permission for two meetings in German cities last week that were part of the Turkish government's campaign to win the Turkish community's support for next month's referendum on the constitution in Turkey.
Germany is home to an estimated three million Turks.
Turkey's Foreign Minister Mevlut Cavusoglu will meet with his German counterpart next week to discuss tensions between the two countries.
Germany claims that the cancelled meeting was a local government decision and not a federal one.