On Thursday, the State Council, France's highest court for complaints against government authorities, ruled that the school ban on the abaya is legal.
It also noted that it had rejected a motion by an association for an injunction against the ban decreed by the government last month.
The association – known as the Action for the Rights of Muslims (ADM) – had argued that the ban was discriminatory and could trigger hatred against Muslims, as well as racial profiling.
However, the top court claimed the ban was not discriminatory toward Muslims, saying that wearing the over-garment “follows the logic of religious affirmation.”
In its ruling, the court said that the decision was based on French law which does not allow anyone wearing visible signs of any religious affiliation in schools.
French schools have sent dozens of girls home for refusing to remove their abayas. According to French Education Minister Gabriel Attal, some 300 schoolgirls defied the ban.
On Monday, President Emmanuel Macron defended the controversial measure, saying there was a “minority” in France who “hijack a religion and challenge the republic and secularism” with it.
However, the French Council of Muslim Faith (CFCM), a national body encompassing many Muslim associations, has argued that items of clothing alone were not "a religious sign."
The new ban has been criticized by many politicians who argue that loose, covering clothing is not a manifestation of religion and that students should not be excluded from classes because of their outfit.