Stella Mccartney will launch a line of eco-friendly sunglasses next year.

The British designer and environmentalist - who is a vegetarian and refuses to use leather or fur in her creations - revealed the new collection will be made of more than 50 per cent natural and renewable materials.

She told WWD: "The greatest challenge was the amount of time that was spent on research and testing to get the best quality product possible with the highest performance in terms of resistance, while still maintaining the style and finish we always try to achieve."

This is not Stella's first sunglasses collection, she released a line in 2009 in collaboration with Luxottica and says it's important to have fun with them.

She explained: "Women have two sets: a classic pair they'll have forever, and a more playful pair. We've added that fun element to the line. 'My mum had this mad pair with Christmas trees on them that I loved when I was little. Sunglasses are one of the only accessories that can really have a sense of humour. But you walk a fine line between looking like a complete idiot and getting it just right."