France's top administrative court has overturned a town burkini ban amid shock and anger worldwide after some Muslim women were ordered to remove body-concealing garments on French Riviera beaches.

The ruling by the Council of State specifically concerns a ban in the Riviera town of Villeneuve-Loubet, but the binding decision is expected to set a legal precedent for all the 30 or so French resort municipalities that have issued similar decrees.

Lawyers for two human rights groups challenged the legality of the ban, saying the orders infringe basic freedoms and that mayors have overstepped their powers by telling women what to wear on beaches.

Mayors had cited concern about public order after deadly Islamic extremist attacks this summer, and many officials have argued that burkinis oppress women.

Lawyer Patrice Spinosi, representing the Human Rights League, told reporters that the decision should set a precedent, and that other mayors should conform to it.

He also said women who have already received fines can protest against them based on Friday's decision.

The mayor of Sisco, in northern Corsica, said he will not lift his ban on the burkini despite the ruling.

Ange-Pierre Vivoni had banned the burkini after an August 13 clash on a beach in Sisco.

He told BFM-TV: "Here the tension is very, very, very strong and I won't withdraw it."

He conceded he does not know whether a woman was actually wearing a burkini the day a clash occurred that set a group of sunbathers of North African origin, from another town, against villagers from Sisco.

It took days to untangle the events leading to the violence that many immediately assumed was over a burkini.