A French court has upheld a school's decision to expel three Sikh boys for wearing turbans to school.
The boys were expelled last November
The tribunal said the boys' continued wearing of an under-turban made them "immediately recognisable as Sikhs".
Under a law passed amid protests in March 2004, French students are barred from wearing conspicuous religious symbols at school.
The boys' lawyers said they would appeal and if necessary take their case to the European Court of Human Rights.
The boys, aged 15 to 18, were expelled from the Louise-Michel school in Bobigny, north-east of Paris, last November.
The three were separated from the rest of the class at the beginning of the autumn term and taught separately.
They appealed against the segregation but in October a French administrative court referred the matter back to the school for further mediation.
Shortly afterwards the boys were expelled as they failed to reach a compromise allowing them to wear the Sikh keski, or under-turban.
The school's decision was confirmed in December by the education authority in charge.
The boys were the first Sikhs to be punished by the new secularity law.
One of the boys' lawyers, Felix De Belloy, had argued that as they had no intention of trying to win converts to their faith, the boys posed no threat to the law.
The French secularity law, primarily aimed at stemming the growing numbers of Muslim girls wearing headscarves in school, also prohibits the wearing of Christian crucifixes and Jewish skullcaps.
The law also outlawed the Sikh turban, although French authorities have admitted they did not consider the Sikh community when the law was being drawn up.
Sikh males are required by religion to allow their hair to grow, and most wear a turban - a symbol of Sikh identity, which helps to keep the growth under control.
In most French schools Sikhs have reached a compromise that has allowed them to wear the keski, a smaller version of the turban, to control their hair.