Teachers at a school in the small French town of Flers have gone on strike, reviving a long-running controversy over the right of Muslim girl pupils to wear headscarves at school.

The teachers say that national regulations lay down that signs of religious observance should not be displayed in state educational institutions.

The latest case involves a 12-year old girl of Turkish origin enrolled in a junior high school, whose father insists that she wear a Muslim headscarf in accordance with the family's religious beliefs.

But, almost without exception, the 70 staff at the school object, arguing that the wearing of the headscarf breaches a 1994 regulation that bans the display of any ostentatious sign of religious allegiance in state educational establishments.

However, before that regulation was introduced, the State Constitutional Council had ruled that Muslim girl pupils were free to wear headscarves, provided they made no attempt to convert their school mates.

Classes in French state schools not only do not have any religious content, the teaching of religion is specifically forbidden.

Teachers and local education authorities have been involved in a series of incidents in recent years involving Muslim pupils, and the Education Ministry has a special mediator to intervene in such cases.

The latest problem has been exacerbated by the decision of the parents of a second girl at the school, who until now has not worn a headscarf, to send her to school with one in future.

Muslim community leaders have in many cases dissociated themselves from parents who insisted that their daughters cover their heads.

Islam is France's second largest religion after Catholicism, estimated at four to five million people, most of them from the former French colonies in North Africa.