A media storm has erupted over the use of halal meat by some of the UK's leading food brands and restaurants.
Halal refers to the process by which an animal is slaughtered before being used for meat, with some religions preferring that they have their throats cut while still alive, although stunning is often used to put them in an unconscious state.
Popular dining chain Pizza Express has begun to use purely halal chicken in its dishes, but customers have complained this is not specified on the restaurant's menus, meaning they are unable to make an informed choice about their food.
However, on its website, Pizza Express said: "It is no secret that all the chicken used in our dishes is halal slaughtered … We're committed to high animal welfare standards and as such the birds are stunned before slaughter.
"The quality, safety and integrity of our products is paramount and our chicken supplier is accredited by the British Retail Consortium."
In light of this, consumers are calling on the food industry to review the way in which meat is advertised and labelled so people are informed about whether or not they are eating halal.
Speaking to the Independent, the RSPCA said it wants consumers to have a choice about what kind of meat they are eating. The charity is also campaigning for changes in the law to improve conditions for all animals at the time of slaughter.
Despite the current controversy regarding a lack of clarity on food labels, many major brands have openly sold halal products on UK shelves for many years.
For example, almost 100 KFC outlets use halal chicken and one-fifth of all Nando's restaurants do. Subway has used halal meat on its sandwiches in selected stores since 2007 and McDonald's considered changing to use it, but decided it would cause too many alterations to its current kitchen operations.
Leading supermarkets including Tesco, Morrisons and Sainsbury's also sell halal products because of the high demand for them due to the country's growing Muslim population, which is expected to reach 5.6 million people by 2030.