UK supermarkets need stronger policies to ensure suppliers do not misuse antibiotics on livestock, campaigners have warned.

The Alliance to Save Our Antibiotics (ASOA) examined published and publicly available information on the antibiotic policies of the UK’s 10 biggest supermarkets.

Farmers in many countries use antibiotics to mitigate the increased risk of disease among livestock in intensive farming conditions.

However, overuse on farm animals can cause bacteria to mutate into superbugs that are resistant to antibiotics, posing risks to human health.

New regulations were introduced in the UK in May to restrict antibiotics in farming so they can no longer be used to compensate for poor hygiene, inadequate animal husbandry or poor farm management practices.

But ASOA found that most supermarkets appear to only have policies that cover their own-brand goods and not branded foods, which can include imported meat, fish, dairy and eggs.

While their policies generally say suppliers must use good animal husbandry and farm management to minimise the need for antibiotics, supermarkets are frequently allowing them to use intensive-farming methods known to cause higher levels of disease and of antibiotic use, the report said.

Coilin Nunan, a policy and science manager at ASOA, said: “Globally, it is estimated that about two-thirds of all antibiotics are used in farm animals.

“Yet supermarkets are often not checking whether imported food they are selling has been produced with routine antibiotic use.

“This is unfair on UK farmers, who are held to higher standards. More importantly, it is a threat to the health of consumers.”

The report, published on Friday, came a day after world leaders met at the UN general assembly in New York on Thursday where they discussed the alarming rise in antibiotic resistance.

The World Health Organisation (WHO) has described the rise of antimicrobial resistance as “one of the top global public health and development threats”.

In its report, ASOA ranked supermarkets on a set of criteria, which included their policies on antibiotic use, the produce these policies cover, whether they have a target to cut antibiotic use and whether they monitor antibiotics in their supply chain.

Marks & Spencer came out on top in the ranking system with Waitrose and Tesco scoring highly in joint second place.

The report found that Marks & Spencer and Morrisons are the only supermarkets to fully ban the powerful antibiotic colistin, which WHO said should be reserved as a drug of last resort for human use.

Meanwhile, Waitrose and Tesco only partly achieved this, the report added.

Most supermarkets continue to sell fast-growing breeds of broiler chickens, which require six to nine times more antibiotics for each bird than slower-growing breeds.

Marks & Spencer is the only supermarket that just sells slower-growing broilers although Waitrose has committed to doing so from 2026.

The other supermarkets examined were Aldi, Asda, the Co-op, Iceland, Lidl and Sainsbury’s.

The report acknowledged that there has been progress in supermarkets’ policies in recent years.

Antibiotic use on UK farms has been reduced by 59% since 2014, and the use of the most critically important antibiotics has been cut by 81%.

But ASOA is calling on all supermarkets to strengthen their animal-husbandry and antibiotics policies across all products.

Dr Ron Daniels, vice president of the Global Sepsis Alliance, said: “Antibiotics are the bedrock on which we’ve built much of modern medicine.

“The stark reality is that multi-drug resistant bugs are causing life-threatening infections in thousands of patients in our hospitals today, with many sadly dying as a consequence of sepsis.

“That’s why all of society needs to urgently come together to address the drivers for rising rates of AMR urgently and cohesively, including addressing our desire to consume meat produced in intensive farming.”

Devina Sankhla, food policy adviser at the British Retail Consortium, said: “BRC members work closely with farmers and suppliers and advocate the principles set by the Responsible Use of Medicines Alliance in Agriculture to ensure antibiotics are responsibly used in food production.

“Suppliers must follow all legal requirements on the acceptable use of antibiotics, balancing animal welfare with the reduction and refinement of antibiotic use in UK agriculture.”

Meanwhile, an Iceland spokesperson said the findings were incorrect, adding that it does not publish its policies publicly but instead directly to its suppliers.

The supermarket’s policies adhere to UK and EU regulations and restrict the use of highest priority critically important antibiotics including colistin.