Tenders to supply a further 10 million doses of avian influenza vaccine for potential use in poultry and other captive birds have been welcomed by Defra.
Ministers were keen to stress that this measure, delivered in a written ministerial statement to the House, does not change the Department's policy.
"The Government has decided to take this step on the advice of the UK Chief Veterinary Officer (CVO) as a precaution," announced Animal Health Minister Ben Bradshaw.
"This does not change our policy and the CVO's advice remains that we should not vaccinate poultry in advance of an avian influenza outbreak because of the well documented limitations of the vaccines currently available.
"These vaccines are not the most effective defence against avian influenza," he said.
"A high standard of biosecurity, separation of poultry from wild birds and careful surveillance for signs of disease are the most effective means of protection.
"The vaccine would also not be used as an immediate disease control response. Early reporting, rapid action, biosecurity, culling and surveillance remain the most effective ways of controlling an avian influenza outbreak."
This step will ensure that Defra has every tool available to tackle an avian influenza outbreak, in light of uncertainties about the future spread and nature of the virus.
The Department has tendered for vaccine which could be used against both H5 and H7 strains of the disease.
But it will only be used if a risk assessment and scientific evidence indicate it would help to prevent disease spread.
A total of 2.3 million doses of vaccine were bought earlier this year for a possible risk-based preventive vaccination of zoo birds.