Cosmetics firms have been warned to stop using false eyelashes and airbrushing techniques to exaggerate the effects of make up as advertising watchdogs have banned a major commercial starring Cara Delevingne.

The Advertising Standards Authority has ruled that a Rimmel mascara advert can no longer be shown as it portrays an unrealistic picture of the "volumising" and "lengthening" impact of the eye make-up.

It is the first major advert to be banned over use of false lashes since 2010 when a Dior advert starring Natalie Portman was ordered to be removed from being shown.

A spokesman at the ASA said the ruling sends a message to other cosmetics firms that they must make it clear if they are using fake eyelashes, or other methods, which artificially enhance the perceived effect of products.

The TV advert for Rimmel's Scandaleyes Reloaded mascara shows model Cara Delevingne running through the streets of London being chased by 'undercover agents'.