"The constitution and equality between men and women prevails over bigotry."

Swiss authorities have defended their decision to deny citizenship to a Muslim couple because the man and woman would not shake hands with the opposite sex during their interview. 

The vice mayor of Lausanne, Pierre-Antoine, a member of the commission that interviewed the couple months ago, told Agence France-Presse Friday that he was “very satisfied with the decision," which he said upholds the principle of gender equality. 

"The constitution and equality between men and women prevails over bigotry," he said. 

In addition to refusing to shake hands, Mayor Grégoire Junod told AFP that the couple “showed great difficulty in answering questions asked by people of the opposite sex." He said their behavior during the interview generally signaled to the three-person commission that they had not adequately integrated into Switzerland.

Despite laws that ensure freedom of religion, “religious practice does not fall outside the law,” Junod said.

Swiss officials would not reveal specifics about the couple, who local media said were North African.  The couple were not asked about their faith, authorities said, though their religion seemed apparent, local media reported. The couple has 30 days to appeal the decision.

Some Muslims do not physically touch members of the opposite sex, with the exception of certain relatives.

Lausanne's decision came amid a ​debate across Europe over how to deal with an influx of Muslims to the continent. The veil worn by some Muslim women has ​become a symbol of the battle over national values. 

Although Muslim immigration is a less pressing issue in the United States, questions about whom should be ​allowed into the country or ​counted as an American have moved to the center of the national conversation in recent years. 

Muslims refusing to shake hands has caused controversy in Switzerland before. 

In 2016, a school accommodated two Muslim Syrian boys who refused to shake a female teacher's hand, which is considered a sign of respect by students. The news caused an uproar and led authorities to overrule the school, saying “the public interest concerning gender equality as well as integration of foreigners far outweighs that concerning the freedom of belief of students."

The students were reportedly brothers whose family worried the controversy would scuttle their citizenship process. 

In April, in neighbouring France, an Algerian woman was denied citizenship after ​refusing to shake the hand of an official during her citizenship ceremony.

On the other hand, a Swedish Muslim woman last week won compensation from a labor court after a job interview was ended when she refused to shake hands.