Livia Firth, VV Brown and Louis Smith have shown their support for Fashion Revolution Day.

A host of eco-conscious celebrities have posed for the inaugural event's new campaign, shot by British portrait photographer Trevor Leighton, turning their clothing insider out in order to call for better transparency across the entire fashion supply chain.

The stars, who also include retail expert Mary Portas, soul diva Mica Paris and eco-journalist Lucy Siegle, are joining forces this Thursday 24 April 2014 with people from over 50 countries to raise awareness for the cause.

Mica commented: ''The fashion industry depends upon people feeling good about what they wear. Fashion Revolution Day is a way to extend the 'feelgood factor' to feeling good about the conditions in which products are created. It's important to ask questions about who makes your clothes, from field to shop, and how they are produced.''

Fashion Revolution Day aims to change people's outlook on their clothes with a challenge dubbed Who Made Your Clothes?.

Everyone can show their support by wearing an item of clothing inside out then posting a picture on social media with the hashtag #insideout.

The event marks the first anniversary of the Rana Plaza factory disaster in Dhaka, Bangladesh which killed 1134 people.