The Food Standards Agency's chief executive, Jon Bell, said in a statement on Friday that the illegal dye, Sudan I, contaminated the food products.

"Sudan I could contribute to an increased risk of cancer," he said. "However, at the levels present, the risk is likely to be very small but it is sensible to avoid eating any more. There is no risk of immediate ill health," Bell added.

The dye, Sudan I, was in a batch of chilli powder used by British tea and pickle maker Premier Foods Plc to make a Worcester sauce that was subsequently used as an ingredient in a range of soups, sauces and ready meals.

The Food Standards Agency said it was working with the industry and local authorities to ensure all the foods are removed from sale. It advised people not to eat the products and to contact the store they bought them from for a refund.

The agency said a list of the affected food products can be found on www.food.gov.uk/sudanlist.

Premier Foods was not immediately available for comment.