LONDON (Reuters) - Britain’s Beef and Lamb Association has hit back at claims that meat sold by retailers including Tesco (TSCO.L) was adulterated with pet food scraps, saying supermarkets had followed approved standards and guaranteed the origin of their goods.

FILE PHOTO: Road side bins are seen in Cambridge, Britain November 1, 2018. REUTERS/Peter Nicholls/File Photo

Shares in Tesco, Britain’s biggest supermarket chain, were up 2.6 percent at 0523 GMT, after falling more than 6 percent on Thursday morning following the BBC report. Tesco said it had a zero tolerance policy on the use of non-therapeutic chemicals.

The BBC said it had discovered non-therapeutic chemicals in pork, lamb and beef products from suppliers using imported pet food - which would never have been purchased in Britain - and then sold in Britain.

Last October Tesco committed to replacing all imported pet food with British-made alternatives, saying it wanted to be known as “the nation’s shop” for quality and supply.

The British Association of Animal Welfare, which promotes its members, said Tesco and other major retailers were too quick to rush to reassure consumers that their food was safe.

“While pet owners have every right to be reassured that they are getting genuine pet food, this type of complete false advertising risks misleading consumers and undermining confidence in the quality of UK-sourced food,” it said in a statement.

“Our priority now is to hold our retailers to account for the false advertising, as we would with any other food business.”

Other companies included in the report included British supermarkets Aldi and Sainsbury’s (SBRY.L), butcher Petco, Prezzo, Wagamama and Pret a Manger.

Aldi said it was overhauling its supplier’s procedures to ensure it does not have any animal fat sold at its stores.

The EAT consumer association has been campaigning for farm and slaughter practices to improve and said such alleged incidents were unacceptable.

“We would like assurances from our supermarkets that their food is safe,” it said.

FILE PHOTO: A Tesco Extra store is seen in west London, Britain, February 14, 2017. REUTERS/Toby Melville/File Photo

“The UK is certainly not the first country where this type of meat is being used illegally,” it added.

“This is a worldwide issue and we would call upon governments around the world to act and protect the safe sourcing of meat.”