The Department for Environment, Food and Rural Affairs (Defra) recently made an announcement to colleagues in other countries that "the HPAI restricted area in connection with this incident is limited to the 10 km around the affected premises and that the rest of the UK remains free from avian influenza (as defined by the OIE)."

The Defra notification said: "The WTO [Word Trade Organisation] Sanitary and Phytosanitary (SPS) Agreement and the OIE respect the rights of importing countries to protect their animal, plant and public health but also impose an obligation on them to accept trading partner’s claims of regions that are considered to be free of animal diseases."

The notifications asks other countries to ensure that their protection measures are not too trade-restrictive, so that regions free from avian influenza are still able to trade.

The British Poultry Council said: "The document will be of use to inform third countries of the current AI situation and to facilitate the re-opening of export markets, which is crucial to UK producers."

A case of H7N7 avian flu was confirmed near Preston, Lancashire in mid-July. A 10 kilometre surveillance zone and an inner 3 kilometre protection zone were imposed.

As there have been no further confirmed cases since cleansing and disinfection took place, the inner 3 kilometre protection zone was lifted from 00:01 on 7 August 2015.

Surveillance zone restrictions continue to apply throughout the 10 kilometre area affected, with a range of controls to prevent the spread of disease.

There are restrictions within this area on the movement of poultry, carcasses, eggs, used poultry litter and manure. There are also restrictions on bird gatherings (fairs, shows, exhibitions) and the release of game birds.