Children use it in class not realising the negative

French schools have launched a crackdown on the African cultural practice of 'teeth-sucking' after teachers complained it was 'extremely vulgar' and offensive.

The practice – known as 'le tchip' in French – produces a hissing sound by sucking air through the teeth from behind pursed lips.

In African and Afro-Caribbean cultures, it widely used to display annoyance or contempt.

'Extremely vulgar': Schools in France are banning the African cultural practice of 'teeth-sucking' because it is offending teachers. The practice produces a hissing sound by sucking air through the teeth and pursed lips

Longer and louder sounds can be used to show even deeper incredulity.

But it can be a popular means of expression among pupils because it can also be done quietly enough to allow deniability.

One French journalist of African descent recently told that she would use it with her peers but never to an elder or an employer.

Many French pupils have adopted the custom in class, apparently not necessarily realising the negative connotations that it carries.

Eric Bongo, deputy headteacher at a high school in Evry, near Paris, said: 'It’s extremely vulgar.

Display of annoyance or disdain: French Justice minister Christiane Taubira (pictured), who was born in French Guiana, made headlines in March when she used the 'tchip' to hit back at her critics in an interview

'I grew up in Africa and when I was young it was forbidden to "suck-teeth" at others.

'I explained this to my colleagues and now it is forbidden at the school, just like any insult, because it is rude.'

His school and others across France have now banned the act, with offenders being thrown out of class, it was reported by The Local, which cited French newspaper Le Parisien.