Britain’s food watchdog admitted yesterday that it could not rule out a risk to human health from the brain disease atypical scrapie, which is similar to BSE.

The advice from the Food Standards Agency raises the most serious concern about the safety of the meat since the discovery of “mad cow” disease in cattle. The new disease is similar to classic scrapie, a brain-wasting disease that has been known in sheep for more than 100 years, but which has never posed health concerns in human beings.

Mutton accounts for a quarter of sheep meat sold in Britain and is commonly used in many meat pies, pasties, curries and some ready meals. The risk from sausages comes from haggis and some upmarket brands that use casings made from sheep’s intestines.

The agency said that it was updating guidance to shoppers because it did not know whether atypical scrapie could affect health.

While it is not advising people to stop eating sheep or goat meat, or their dairy products, it makes clear that consumers can reduce the risk of a new disease.

However, shoppers will find it difficult to identify mutton products because there is no requirement to label it, except for pre-packed sausages. There is also no legal definition of what comprises mutton.

The agency is to ask the European Commission for the urgent introduction of new labelling rules that would mean manufacturers would have to identify products containing mutton.

Proposed new advice, to be discussed by the Food Standards Agency tomorrow, says: “While the agency is not advising anyone to stop eating sheep or goat meat or products, any possible risk could be reduced further by not eating meat from older animals.”

It adds: “In addition, some sausages are contained in natural sheep casings made from sheep intestines which are more likely to carry the disease agent and therefore could present a greater risk.”

Atypical scrapie is now identified in the national flock — there could be as many as 82,000 cases — and it has been found in sheep throughout Europe.

The move threatens to derail a new offensive from the Prince of Wales to bring about a renaissance in mutton eating. Peter Morris, chief executive of the National Sheep Association, said last night that the agency advice would trigger a new food scare.

“It runs the risk of people not eating mutton and sends out negative messages about mutton, when there is no proven risk.

“The Prince of Wales is such a keen supporter for the revival in mutton I am sure he will be among the first to put out the message that people should keep potential risks in proportion and keep eating mutton.”

Peter Ainsworth, the Conservative rural affairs spokesman, said: “We need to be cautious about any threat to human health. But there is a real danger that a message of this kind will create serious difficulties for sheep farmers at a time when they least need further problems from government agencies

“It’s incredibly important that the FSA behaves in a measured and appropriate manner.”

The 8,000 tonnes of British mutton eaten each year in Britain is worth about £400 million a year.

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