Nearly a third of British farms could become infected with foot-and-mouth disease, scientists have warned.
Experts from London's Imperial College School of medicine say the firebreak culling of healthy cattle near infected sites must be intensified.
They claim the Government has not met its target of killing all animals on farms neighbouring an infection site within 48 hours of an outbreak being confirmed.
They claimed that, even when infected animals were slaughtered within 24 hours of symptoms appearing, some 30 per cent of all UK farms would eventually be hit by the epidemic.
They predicted that pre-emptive "ring culling" - which is the slaughter of all animals within a certain distance around the outbreak area - is the only way to prevent this figure being reached.
Writing in the journal Science, the researchers used data from the British ministry of agriculture, fisheries and food to produce a mathematical model of disease transmission.
Researchers Neil Ferguson, Christl Donnelly and Roy Anderson said the intensive culling programme should be maintained even when the epidemic started to retreat.
Their 30 per cent infection prediction for farms rose to 79 per cent in the heavily infected areas of Cumbria and Dumfries and Galloway.
Killing sick animals within 24 hours and then ring-culling over a 1.5 kilometre area within 48 hours would protect "many more farms".