Conservative MPs are lobbying for a change in the law which would force restaurants and supermarkets to label their meat if it is halal or kosher.

The move by Conservative backbenchers comes as it was revealed this week that several major food and drink chains including Pizza Express, Ask and Costa have been serving halal meat without informing customers on their menus.

In a letter published in the Daily Telegraph newspaper yesterday, Shechita UK chairman Henry Grunwald and Muslim Council of Britain deputy general secretary Dr Shuja Shafi defended Jewish and Muslim practices.

The faith leaders argued that comprehensive labelling rules on all methods of killing animals should be applied to provide consumers with a “genuine choice”.

There are indications that members of the Coalition are split over the issue with David Cameron and Nick Clegg disagreeing over whether the government should intervene to ensure clear labelling.

An official spokesman for the Prime Minister said: “ We understand why some consumers may have concerns about the information that is provided to them. In terms of this type of information, the Prime Minister’s view is that it is one for retailers and restaurants … in discussion, of course, with their customers and representatives of faith groups.”

But Deputy Prime Minister and Liberal Democrat leader Nick Clegg said that while he had no problem with eating halal meat, he thought it would be “relatively straightforward” for businesses to inform their customers.

Philip Davies, the MP for Shipley, who tabled the change to the Consumer Rights Bill, said: “What we’ve seen in far too many cases is people unwittingly buying a product that they don’t want to buy. That’s not acceptable. It’s all about consumer choice.”

The amendment to the bill has also been supported by Julian Sturdy, the MP for York Outer, and Philip Hollobone, the MP for Kettering.

The RSPCA and British Veterinary Association have called for mandatory stunning which would go against the rules of kashrut, but not some halal practices which sometimes also include the stunning of animals.