A controversy has erupted in Italy over a court ruling ordering a state kindergarten to remove crucifixes from its classrooms.
The law on crucifixes in schools dates back to the 1920s
A judge in the central town of L'Aquila upheld a complaint by an Italian Muslim leader, Adel Smith.
The ruling has re-opened a bitter debate about religious symbols.
Italy's Justice Minister said he would order an inquiry into whether the decision conformed with Italian law.
BBC's Frances Kennedy in Rome says the case is set to have far-reaching implications
It centres on a nursery and primary school near L'Aquila, about 100 kilometres (60 miles) from Rome.
The president of a Muslim group, Adel Smith, initially suggested that a symbol from the Koran should be displayed alongside the crucifix in his children's classrooms.
When this was denied, he took his complaint to the courts.
The judge ruled that the crucifixes showed "the unequivocal desire by the state, when it comes to public education, to place the Catholic religion at the centre of the universe", in disregard for other religions.
The school has 30 days to carry out the judge's order and remove the crucifix.
"I have no fight with the crucifix," said Mr Smith after the ruling. "I have simply been granted a constitutional right that religious symbols should not be on display in the classroom where my children study."
The decision was welcomed by one teachers' union, saying it was a reinforcement of the secular character of the education system.
But the ruling has shocked the Roman Catholic Church.
remove a symbol of the religious and cultural values of a people just because it can offend someone," said a leading prelate, Cardinal Ersilio Tonini.
A number of government ministers were similarly outraged.
"It is unacceptable that one judge should cancel out millennia of history," said Labour Minister Roberto Maroni.
Justice Minister Roberto Castelli threatened sanctions if an inquiry concludes the court ruling does not conform to Italian law.
Church and state
Several Italian newspapers have compared the case to the controversy in France over moves to ban Islamic headscarves in schools.
The decision by the judge in L'Aquila could increase tensions between Catholics and atheists, and between Christians and Muslims, said La Repubblica on Sunday.
Italy has a rapidly growing Muslim population - mainly of recent immigrants - which is put at more than one million, according to the latest estimates.
Adel Smith launched the controversial case
The law requiring crucifixes to be hung in schools dates back to the 1920s, when Catholicism was state the religion in Italy.
Although a revised accord between the Vatican and the Italian Government ended Catholicism's position as state religion in 1984, the crucifix law has never been repealed.
However, the presence of crucifixes in classrooms is left to individual head teachers.
Last month, Education Minister Letizia Moratti said the cross should remain in state schools and hospitals.
She also endorsed controversial funding for Catholic schools.