Farmers said on Friday they would launch a legal challenge if the farm ministry rejected as expected next week a badger cull to help tackle bovine tuberculosis in cattle.

Farm minister Hilary Benn told reporters he would announce a decision on Monday and the BBC reported the ministry was poised to reject a cull on badgers, a wildlife host of the disease.

Peter Kendall, president of the National Farmers Union, said in a statement the farmers' group would seek immediate legal advice to challenge any negative ruling in court.

"Last year saw 28,000 cattle culled with TB, and already in the first quarter of 2008 another 13,500 cattle have been lost. This sort of needless waste of productive animals . calls into question the government's attitude not only to food security but also to animal welfare," he said.

Bovine TB is a chronic debilitating disease which causes breathing difficulties and ultimately death. It can spread to humans, with similar symptoms to the human form of the disease, but such cases are very rare.

Many farmers believe a cull on badgers is needed to tackle the spread of the disease, but there has been strong opposition from wildlife groups.

Scientific opinion is divided.

Former government chief scientific advisor David King has said a badger cull could make a contribution.

However, a report by the farm ministry's Independent Scientific Group concluded "no practicable method of badger culling can reduce the incidence of cattle TB to any meaningful extent and several culling approaches may make matters worse".

Wildlife advocacy group the Badger Trust welcomed reports a cull would be rejected, adding "there is no scientific, economic or practical case for culling badgers to control bovine TB."

Bovine TB occurs worldwide with Ireland, Spain, Italy, Portugal and Greece among other European countries where it remains a problem.