There have been several cases of vets clinically identifying the disease in wild deer, some of which have died from it. There have also been many reports from Devon, Cumbria and Northumberland of deer limping and exhibiting other unusual behaviour linked to the disease.

Veterinary experts say it is impossible to vaccinate or cull wild deer and once infected they will act as a reservoir for the virus, repeatedly re-infecting livestock. It will make it almost imposs-ible for Britain to rid itself of the virus, until it dies out naturally in wild deer, which could take years.

Last week a roe deer was found dead at Kirk House Farm near Penrith, which had already been confirmed as having foot and mouth in livestock. Local vet Matt Coulston, of Frame Swift and Partners, identified lesions on all four feet and in its mouth. 'It had signs consistent with foot and mouth disease,' he told The Observer. 'There have been loads of people round here reporting dead deer and sick deer. People suspect that Maff [the Ministry of Agriculture, Fisheries and Food] are ignoring it because it is difficult to deal with.'

The British Deer Society has been flooded with reports from deer experts reporting the animals limping and being covered with lumps. Mike Squire, secretary of the society, said: 'We find it difficult to believe that deer exposed to the same pastures as infected cattle and sheep have not been exposed to foot and mouth disease.'

A Maff spokesman said yesterday that government vets had tested nine deer for foot and mouth and none had been found positive: 'So far there have been no confirmed cases of foot and mouth in deer.'

However, the Maff vets use the Elisa test, which was developed on cattle and sheep and is not thought to be so effective on deer. Research from Russia also suggests it is very difficult to test whether deer have been infected with foot and mouth from blood samples.

In 1974 the government Animal Health Institute in Pirbright kept a number of deer in proximity to sheep with foot and mouth for two hours in a controlled experiment. The scientists found all six native species of deer contracted the disease, and several died.

In an outbreak of foot and mouth in California in 1924, the outbreak spread rapidly to deer. Slaughtermen culled 22,000 deer in the Stanislav National Park and found that, of those, 2,279 were infected.

Dr John Fletcher, past president of the Veterinary Deer Society, said: 'It's highly likely the virus has entered the wild deer population - the deer are in abundance and graze in close contact with sheep and cattle. Nothing has been confirmed, but there is an abundance of anecdotal evidence, and it would be quite surprising if it hasn't entered the population.'

Simon Booth, director of the Deer Inititiative, the government advisory body on deer in England, said: 'There have been unconfirmed cases of it appearing in deer.'

Deer experts have been calling on Maff for weeks to conduct a selective deer cull to ascertain the extent of the disease and to draw up contingency plans. However, Maff ignored their warnings until it called an emergency meeting on Friday. It is now considering lifting the ban on deer-stalking to provide the carcasses for tests.

The existence of the disease in Britain's 1.5 million wild deer population means the policy of mass slaughter of more than a million farm animals and the closure of most of the British countryside has been pointless. Wild deer are so evasive and diffi cult to track down that it is impossible to vaccinate or cull them. Shooting at herds of deer will simply cause them to run, spreading the disease further.

The deer population will harbour the disease before building up resistance and it eventually dies out. This could take years. Until then the deer will repeatedly re-infect livestock and, with the disease endemic in Britain, meat exports will continue to be banned.

Squire said: 'We're looking at a huge slaughter and cost to the taxpayer for no purpose. How do you think the public will react when they know that?'

Booth said: 'If it's in the deer population, it will mean the mass slaughter policy will not work.' Confirm-ation of foot and mouth among deer will force the Government to abandon the mass slaughter programme, a move that has been steadfastly resisted by the National Union of Farmers. 'It will force their hand into vaccination,' said Fletcher.