An influential consumer rights association on Wednesday urged a court to ban the sale of Perrier bottled water in France, saying the brand's claim that its product is "natural" was misleading.

UFC-Que Choisir, which lodged its request with a court in Nanterre near Paris, said the Nestle-owned Perrier brand should be banned temporarily from selling its sparkling water and be ordered to stop its "dishonest" description of the water.

"Consumers buy water that is sold as natural mineral water but it isn't natural because it has been treated," the association's lawyer Alexis Macchetto told AFP.

In early 2024, media reported that Nestle Waters -- which also owns the Vittel and Contrex brands -- had deployed banned processes to improve its quality, including ultraviolet treatment and activated carbon filters.

Such treatment is contrary to French and European law which states that natural mineral water cannot undergo any processes that changes its original state.

Nestle Waters told AFP Wednesday that it would contest UFC's complaint, adding it had always "operated under official control".

But UFC argued that the alteration of the water carried health risks. "If nothing is done, somebody could fall ill", said Macchetto.

Perrier is obtained from a spring in southern France.

Contamination by bacteria from fecal matter has been found on several occasions in the wells supplying Perrier, especially following heavy rainfall.

Nestle Waters has argued that such incidents have been rare, and that it was no longer using the affected wells.

But Macchetto said Nestle's recent decision to replace its 0.2 micrometre filters with 0.45 micrometre filters heightened risks for consumers because the change made filtering "obviously less efficient".

The controversy took a political turn earlier this year, when an investigation by France's upper house of parliament found that the government "at the highest level" had covered up a scandal over the treatment of mineral water by Nestle.

The commission alleged that President Emmanuel Macron's office "had known, at least since 2022, that Nestle had been cheating for years".

The Swiss conglomerate had been already been under pressure over Perrier and its other brands as EU regulations strictly limit what treatments are allowed for any product marketed as natural mineral water.

In 2024, Nestle Waters admitted using banned filters and ultra-violet treatment on mineral waters.

The company paid a two-million-euro ($2.2-million) fine to avoid legal action over the use of illegal water sources and filtering.

In June of this year, Nestle Waters was fined more than $610,000 in Switzerland for having used activated carbon filters on its Henniez bottled mineral water.