PARIS (AP) — France’s top administrative court ruled Tuesday against allowing body-covering “burkini” swimwear in public pools for religious reasons, arguing that it violates the principle of government neutrality toward religion.

While worn by only a small number of primarily Muslim women in France, the burkini draws intense political debate in the country.

The city of Grenoble, led by a mayor from the Greens party, voted to allow women to wear burkinis in public pools after campaigning by local activists. At the same time, the city also voted to allow women to swim topless as part of a broader relaxation of swimwear rules.

The prefect, or top government official, for the Grenoble region blocked the burkini decision, arguing it ran counter to France’s secular principles.

The Council of State upheld that decision, saying in a statement that the Grenoble vote was made “to satisfy a religious demand” and “harms the neutrality of public services.”

Clothing rules in public pools in France are strict, for what authorities say are reasons of hygiene: caps are required, and baggy swim trunks or other voluminous clothing generally banned.

A few other cities and towns allow burkinis in public pools. The city of Rennes is among them, but its decision was aimed at loosening swimwear rules generally and not based on religious reasons.

Grenoble's decision about swimming topless has not been threatened in the courts.