ZURICH (Reuters) - Switzerland’s highest court has upheld the canton of Zurich’s decision to refuse permission for an Islamic society to open a religious kindergarten, saying its plans did not fulfill the legal requirements for such schools.

The Federal Court’s ruling highlights increasingly tense relations between traditionally Christian Swiss society and a Muslim minority that makes up around 5 percent of the population.

The lower house of parliament in September narrowly backed a ban on face veils, a step widely supported in opinion polls.

A school’s decision this year to let two Muslim pupils not shake their teachers’ hands added fresh fuel to a debate about integration of immigrants.

The “al Huda” society had sought since 2013 to open a kindergarten and appealed against local authorities’ refusal to grant permission. The Federal Court said it had rejected the appeal.

“Overall, the kindergarten concept does not guarantee that the children to be taught will be nurtured in a manner comparable to that of a public school,” said a court summary of the verdict published on Friday.

“There is also a lack of commitment to the humanistic and democratic values of public schools.”

It said teachers of Arabic and the Koran at the planned kindergarten did not have recognized certificates and were over-represented on the faculty, making up a quarter of the staff.

Kindergarten organizers did not immediately respond to an email seeking comment. After earlier legal setbacks, the group said local authorities had treated them unfairly and it hoped the high court would resolve the issue quickly and justly.