Conservative members of German Chancellor Angela Merkel's ruling coalition quickly rejected remarks by Interior Minister Thomas de Maiziere that he was willing to discuss the possibility of introducing Muslim holidays in parts of the country.
During an election rally in the state of Lower Saxony on October 14, Maiziere said, "Where there are many Muslims, why shouldn't we consider a Muslim holiday?"
The CSU, the Bavaria-based sister party of Merkel's Christian Democratic Union (CDU), pushed back at the suggestion.
"Germany's Christian heritage is not negotiable," Alexander Dobrindt, a senior CSU politician, told the Bild newspaper.
"For us, the introduction of Muslim holidays is out of the question," he said.
Senior CDU member Wolfgang Bosbach told Bild that people were free to celebrate whatever religious festivals they wanted in Germany. He added, though: "Whether the state should also protect non-Christian holidays with legal regulation in future is a different issue entirely."
Some 4.4 million Muslims, many from the nation's ethnic Turkish community, live in Germany, which has a total population of about 80.6 million.
Germans will vote on October 15 in a regional election in Lower Saxony, the fourth-largest German state by population.
It is considered a major test for Merkel after she won a fourth term in national elections last month without a parliamentary majority.
Polls show the CDU lagging behind the Social Democratic Party (SPD) in the state.