Burger King has unveiled a 'meatless Whopper' burger in a bid to entice more vegetarians to visit the fast food chain.

The company announced on Monday that it was trialling Impossible Whoppers, made with plant-based patties from Impossible Foods, in 59 restaurants in the city of St Louis. If the trial proves successful, Burger King says it will roll out the Impossible Whopper nationally.

The vegetarian Whopper is intended to taste just like Burger King's signature Whopper sandwich. Unlike existing veggie burgers, the 'Impossible' products are designed to mimic the look and texture of meat when cooked.

The Silicon Valley based startup behind the product, Impossible Foods, says it uses modern science and technology to create wholesome and nutritious food which can feed a growing population without the environmental impact of livestock.