A group of serving French soldiers has published a new open letter in a conservative magazine, warning President Emmanuel Macron that the “survival” of France is at stake after he made “concessions” to Islamism.

The letter posted on the Valeurs Actuelles website late on Sunday echoes the tone of a similar letter published by the same magazine last month, which also warned that a civil conflict was brewing.

Interior Minister Gerald Darmanin, a close ally of Macron, slammed the letter as a “crude manoeuvre” and accused its anonymous signatories of lacking “courage”.

Read: French Muslims, stigmatised by attacks, feel under pressure

The previous letter, signed by a handful of officers and some 20 semi-retired generals, sparked a furore in France, with the prime minister calling it an unacceptable interference and France's top general vowing that those behind it would be punished.

It is not clear how many people are behind the current letter or what their ranks are.

In contrast to the previous letter, it is also open to be signed by the public, with Valeurs Actuelles saying more than 93,000 had done so by Monday morning.

“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,” said the letter, which was addressed to Macron and his cabinet.

The authors described themselves as active-duty soldiers from the younger generation of the military, a so-called “generation of fire” that had seen active service.

“They have offered up their lives to destroy the Islamism that you have made concessions to on our soil.”

They claimed also to have served in the Sentinelle security operation within France launched after a wave of jihadist attacks in 2015.

They observed that for some religious communities “France means nothing but an object of sarcasm, contempt or even hatred”.

It added: “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.”

'Is this courage?

The letter comes in a febrile political atmosphere ahead of the 2022 elections when Macron's main challenger is expected to again be the far-right leader Marine Le Pen.

Analysts say Macron has tacked to the right in recent months to prevent Le Pen from exploiting a series of attacks in late 2020 blamed on Islamist extremists who recently immigrated to France.

“I believe that when you are in the military you don't do this kind of thing in hiding,” Darmanin told BFM television. “These people are anonymous. Is this courage? To be anonymous?”

Read: French generals spark backlash with warning of ‘civil war’

Former president Francois Hollande weighed in on the debate, expressing bewilderment that such sentiments could be expressed by serving soldiers.

“How can we suggest that the army today could have such feelings and a desire to question the very principles of the Republic?” he told France Inter radio.

Prime Minister Jean Castex had labelled the rare intervention in politics by military figures in last month's letter “an initiative against all of our republican principles, of honour and the duty of the army”.

France's armed forces chief of staff, General Francois Lecointre, said those who signed it would face punishments ranging from forced full retirement to disciplinary action.