The government is considering a vaccination programme to buy time in the fight against the foot and mouth outbreak.

Chief vet Jim Scudamore confirmed at a briefing on Friday that the total number of outbreaks had risen to 489 cases with 482,000 "plus" animals set to be slaughtered. More than 318,000 animals have been confirmed with 163,000 classed as dangerous contact.

Nick Brown announced that the government is widening the cull of all animals within two miles of an outbreak across the country to act as a "fire wall". The government is also speeding up efforts to reduce the time between disease being reported and animals being killed. He is also considering the use of a vaccination programme in Cumbria as there are not enough resources to get ahead of the disease.

"It could buy time," said Brown. "All of these issues are under consideration and I emphasise the urgency of it. We are not changing policy but implementing it as thoroughly as possible."

The government's chief scientist, Professor David King, told journalists "we can say that currently looking at Great Britain as a whole, the situation is not under control. If we alter the report to cull time to 24 hours and bring in a three kilometre fire wall the disease can be brought under control."

European leaders on Friday offered their support to the UK government in its effort to combat the disease.

Representatives of the French and Finish governments said they would offer veterinary assistance.

Speaking to the EU leaders, Tony Blair gave a frank assessment of the scale of the crisis - which has now spread from the UK to Ireland and Holland.

Lionel Jospin, the French prime minister, said he would commit vets from the country's national veterinary service. France has also suffered one outbreak of foot and mouth disease but managed to contain and eradicate it.

Cases of foot and mouth could ultimately exceed 4,000 according to research carried out by the government. Researchers from London's Imperial College have estimated that the outbreak is likely to continue into June with major increases very eight days. They also warned that every day where delays occur will add "significantly" to the end date of the crisis.