France's government hit out at a group of serving French soldiers who published an open letter claiming a civil war was brewing due to President Emmanuel Macron's handling of Islamism.
Interior Minister Gerald Darmanin said the anonymous signatories lacked courage, while Prime Minister Jean Castex labelled it a political manoeuvre by the far right.
Defence minister Florence Parly described the letter as part of a “crude political scheme”.
"It uses all the rhetoric, the vocabulary, the tone, the references which are those of the extreme right,” she told TV channel BFM.
"I believe that when you are in the military you don't do this kind of thing in hiding," Mr Darmanin said. "These people are anonymous. Is this courage? To be anonymous?"
But far-right political leader Marine Le Pen, expected to be Mr Macron’s main challenger in next year’s presidential election, welcomed the letter and said civil war was always a risk.
"It is clearly not a call to insurrection," she said. "Otherwise I would not be supporting it."
The letter, published by the magazine Valeurs Actuelles, was signed by an unknown number of soldiers.
"We are not talking about extending your mandates or conquering others. We are talking about the survival of our country, the survival of your country," it said.
The soldiers said they came from a younger generation of soldiers who had been involved in active service.
"They have offered up their lives to destroy the Islamism that you have made concessions to on our soil," the letter stated.
It claimed that, for some religious communities, "France means nothing but an object of sarcasm, contempt or even hatred".
"If a civil war breaks out, the military will maintain order on its own soil … civil war is brewing in France and you know it perfectly well".
It followed a letter last month that offered similar warnings, signed by about 20 semi-retired generals and 80 other officers.
Mr Macron’s government recently set out its “anti-separatism” bill, which aims to clamp down on extremism and values deemed at odds with France’s constitution.
While it has been criticised by some for unfairly targeting Muslims, others argue it has not gone far enough.
France's upper house has added a number of amendments to the bill, including banning the hijab for under-18s in public.