Groups defending the French language have lodged legal protests over the English-only slogan used for Paris's 2024 Olympic bid.
Lawyer Emmanuel Ludot said he has submitted a request with the government's rights defence authority to suspend use of the slogan "Made for Sharing".
He also submitted a warning to the bid committee that the slogan could violate a law on protecting the French language.
Mr Ludot said the language groups want the slogan to be in both French and English, or in French only.
He added: "We want them to communicate in the language that is ours."
The International Olympic Committee will choose in September whether to host the games in Paris, Budapest or Los Angeles.
The Paris bid team responded by saying it is "astonished by certain reactions" and maintained its right to "communicate on an international level".
Earlier this month, the Paris bid's international campaign was projected on to the Eiffel Tower, in English and French.
The slogan "Venez partager" was the French equivalent for "Made for Sharing".
"We are extremely committed to the promotion of our country, of its values, of the French language," Paris 2024 bid director Etienne Thobois said in a statement.
"In order to win, you have to bear in mind that the IOC members who will vote ... won't be French.
"That's why, like all the organisations who speak to an international audience, we made the choice to express ourselves in French and in English. This enables us to directly share our project as much as possible."