It is Iran’s answer to the Academie Francaise, keeping the Farsi language safe from the corrupting influence of foreign words. Its latest, unlikely target: something called “Nutella Bars”.

The state-run Academy of Persian Language and Literature has imposed a number of changes in recent years, particularly aimed at curbing the intrusion of English. Its success has been varied.

Most people now use the Farsi word “balgard” (meaning “spinning wings”) instead of “helicopter”.

But practically no one — except perhaps newsreaders on state television — calls their fax machine a “durnegar” (meaning “distant message-receiver”), or uses “rayaneh” (“organising machine”) when they mean “computer”.

The Academy’s latest target has caused some bafflement: a popular chain of waffle and crepe cafes called Nutella Bars after the Italian hazelnut and cocoa spread in which they smother their snacks.

“The authorities said the signs must change. They are very strict about it,” said a staff member at one branch, asking not to be named. To the amusement of many on social media, the Academy of Persian Language and Literature suggested the chain rename itself “Hot Bread, Hot Chocolate” in Farsi.

“Unfortunately, places called Nutella Bar have recently been spreading in Tehran,” wrote the head of the Academy, Golamali Hadad Adel, in a letter to police last month. “The Academy proposes the use of ‘Hot Bread, Hot Chocolate’ for these shops.”

Several branches around Tehran have already taken down the original logos, although they do not appear keen on the Academy’s name suggestion.