Britain has ordered 3.5m doses of a vaccine against the H5N1 avian bird flu virus in the hope that immunising key workers will help protect them if a mutated pandemic strain arrives in this country.

There is no evidence of how well the vaccine might work, and Conservative spokesman Andrew Lansley accused the health department of being "woefully complacent" about the dangers posed by avian flu.

There were fears yesterday that it had appeared for the first time in a poultry flock within the EU, and thousands of birds have died at a turkey farm in eastern France.