Public schools in France have been turning away students for breaking a new national ban on the abaya, a long, robe-like garment often worn by Muslim women, as a rights group filed an appeal against the prohibition.

A total of 67 girls returned home rather than remove their abayas, Education Minister Gabriel Attal told CNN affiliate BFMTV on Tuesday.

Across the country a total of 298 pupils arrived at school wearing abayas, but a "large majority" agreed to remove them, said Attal, who added that the new rule had been followed "without any major difficulty to report" as the country's schools began the new academic year on Monday.

Attal announced the ban on abayas in schools on Sunday, but by Tuesday the State Council, France's highest court for complaints against state authorities, had heard an appeal from the Action Droits Des Musulmans (ADM) group.

The group's lawyer, Vincent Brengarth, told journalists before the hearing that the ban is "not based on any legal text."

In a separate interview with CNN affiliate BFMTV on Tuesday evening, Brengarth said the ban has been imposed in an "arbitrary" manner as it contains no legal definition of what an abaya looks like. Abayas have also never been formally classified as religious items, according to Brengarth.

"The main argument is that the abaya is not defined by the executive government and the executive power. This is a ban which has absolutely no justification," Brengarth added.

ADM is arguing that the ban infringes on "fundamental rights," such as the right to personal liberty.

France's administrative law requires a decision on the appeal to be handed down by the State Council within 48 hours of the hearing, which ended on Tuesday.

The ban has its legal foundation in a law passed in 2004 banning the wearing of "conspicuous" religious symbols in schools.

As some question whether the abaya is in fact a form of religious dress, lawyers have warned schools to be careful not to penalize students for wearing garments that do not have a clear religious affiliation.

This comes after a student in Lyon was banned from class on Wednesday for wearing a "kimono."

In a post on "X" (formerly Twitter), lawyer Nabil Boudi said he was filing a complaint on behalf of the student, stressing that "nothing in the wearing of a kimono characterizes an ostensible manifestation of belonging to a religion as per the definition of the law of March 15, 2004."

Yara, a 15-year-old student at a school in Lyon, southwest France, told the Agence-France Presse news agency that she does not consider the abaya a form of religious dress.

"They say that the abaya is a religious dress, but it's not at all, it's not a religious dress, it's a traditional dress, it's a dress that all girls wear, both veiled and non-veiled, and so it's a bit of a problem," she said.

A fellow student named Luke agreed that he didn't consider the abaya a religious garment. "You can wear it as a dress, as an everyday garment... it shouldn't have been banned," he said.

And Julie, 16, said there were "more important" issues to be tackled in French schools.

Teachers at one school on the outskirts of Paris say they will strike over the ban, which they describe as Islamophobic, BFMTV reports

In a statement, teachers at the Lycée de Stains in Seine-Saint-Denis also said the ban is deflecting from the "attacks that are being carried out against the public education system," pointing to shortages in teaching personnel and budgetary cuts.

French President Emmanuel Macron has defended the ban, saying it is not "stigmatizing" anyone but "people who push the abaya" are.

Speaking to video blogger Hugo Travers on Monday evening, Macron said schools in France are "free, secular and compulsory" from primary school up to the end of high school.

Macron also said that French authorities will be "uncompromising" in their enforcement of the ban, which is the latest in a series of contentious restrictions in the country on clothing associated with Muslims.