Paris - A simmering controversy over burkinis - a type of head-to-toe swimsuit favored by conservative Muslim women - has roared back to life in France. This week, the southwestern city of Grenoble approved the use of burkinis in public pools, but the French government says it will challenge the ruling.
The move revives long-running tensions about Islamic apparel and the country's staunchly secular values.
Interviewed on French radio, Greens Mayor Eric Piolle said it was important that all city dwellers could access public services - including pools.
The ruling allows women to swim in burkinis but also topless.
The mayor's views aren't universally accepted. Dissenters on the Grenoble city council say Piolle had no authority to pass the measure. The conservative regional council head for the Auvergne-Rhone-Alpes area has suspended subsidies to Grenoble, saying the burkini a sign of women's submission and political Islam.
Now, French Interior Minister Gerald Darmanin says he will challenge the Grenoble swimsuit decision in court, calling it an unacceptable provocation. Even members of Piolle's leftist party are divided over it.
This is not the first time burkinis have caused a splash in fiercely secular France. They were banned on Marseille beaches a few years ago - until a French court overturned the move, judging it discriminatory.
Burkini bans in French public pools are different - they're based on hygiene grounds which also prohibit men's long swim trunks.
But burkinis also fit into a hot debate over France's 1905 law separating religion and state, and simmering fears of political Islam. France bans headscarves in public schools and for female French Football Federation players competing in matches. The face-covering niqab is banned in all public spaces.
A recent poll by the conservative C-News channel found most French oppose burkinis in public pools, but some swimmers don't care.
'Everyone should be free to wear what they want,' says Marie, who was swimming at a public pool in Paris. 'So long as it's not imposed on me, it's not a problem.'
That also seems to be the attitude in the Brittany city of Rennes. A few years ago, local authorities quietly changed pool rules allowing all kinds of swimsuits, including burkinis. Initial controversy soon quieted down. Now, of the thousands swimming in Rennes public pools each year, local government says, just over a handful wear burkinis.