French grammar is sexist, according to hundreds of French teachers who insist they will no longer mark alternatives to male-dominated rules as wrong.

The call from 314 French teachers placed them on collision course with the Académie Française, the hallowed guardians of the French language, which has warned that moves to make French more gender-neutral is placing it in "mortal peril".

The call to arms from across the educational establishment came amid soul-searching in France over wider gender inequality in society in the wake of the Harvey Weinstein sexual harassment scandal.

In an op-ed in the slate.fr, the group said the time had come to turn the page on rules that stipulate that "masculine trumps feminine" when it comes to plural nouns.

Under the standard rules, a male and a female friend are described as “amis”. Two or more friends are called “amies” only when no men are included.

The teachers point out that the rule dates back to the 17th century but was only imposed en masse when primary schooling became compulsory in the late 19th century.

Above all, it was applied for "political" rather than linguistic reasons, they argue, citing a 17th century work by linguistic state advisor Dupleix on French linguistic "purity". This reads: "Because the masculine gender is more noble, it takes precedence alone against two or several feminines, even if these are closer to their adjective."