All keepers of poultry and captive birds have been ordered to implement measures to protect against a dangerous strain of bird flu circulating in Europe.

Government chief vet Nigel Gibbens has declared a "prevention zone" for England, with requirements for commercial and individual poultry and captive bird keepers to keep their birds inside, or take steps to separate them from wild birds.

A type of highly pathogenic avian flu, H5N8, has been found in dead wild birds in countries across Europe, from Poland to France, although no cases have been found in the UK.

The move to declare a prevention zone is a precautionary measure to protect against the risk of infection from wild birds, and will remain in place for 30 days, the Department for Environment, Food and Rural Affairs (Defra) said.

The threat to humans from the bird flu strain remains very low, Public Health England (PHE) said.

Defra said it had increased its surveillance for the disease, and keepers are being urged to reinforce measure such as disinfecting clothing and equipment and making sure feed and water is not accessible to wild birds to prevent infection.

Professor Gibbens said: "While no cases have been found in the UK, and PHE advises the public health threat is low, we are closely monitoring the situation across Europe and have scaled up surveillance in response to the heightened risk.

"As a precaution, and to allow time for poultry and captive bird keepers to put in place appropriate biosecurity measures, we have declared a 30-day prevention zone to reduce the risk of infection from wild birds."

He added: "Even when birds are housed a risk of infection remains so this must be coupled with good biosecurity - for example disinfecting clothing and equipment, reducing poultry movement and minimising contact between poultry and wild birds."

Poultry keepers are being advised to be vigilant for signs of bird flu and to call their vet promptly if they have any concerns.

Members of the public are also being asked to report cases of dead wild waterfowl such as swans, geese and ducks, or gulls, or five or more dead birds of other species to Defra.