"Germany has no superior in the spheres of rule of law, tolerance and liberality," Altmaier told the ARD broadcaster, adding that the Erdogan’s statement was "absolutely unacceptable."
He said that the German government was in permanent contact with the Turkish authorities.
"We will make efforts so that people in Turkey realize and draw conclusions from the meaning and problematics of the events that occurred in the recent days," Altmaier said.
The Turkish referendum on constitutional changes would take place on April 16.
“On behalf of the chancellor and the whole federal government of Germany I would like to comment on some Turkish remarks. We are firmly rejecting equalizing the policy of democratic Germany and Germany in the National Socialism era. Comparisons with Nazi Germany are always absurd,” German government spokesman Steffen Seibert said on Monday.
He pointed out that Germany wanted to have good relations with Turkey although the countries had many sharp disagreements.
Two cities in Germany withdrew last week their permissions for Turkish rallies that were to be addressed by Turkish justice and economy ministers. Ankara is seeking support of its large expat community in Germany for a constitutional change that would give more powers to Erdogan, including granting the president the ability to appoint some top judges and declare a state of emergency.