President Jacques Chirac urged French people not to panic after the presence of the deadly H5N1 strain of bird flu was confirmed at a farm in the east of the country where thousands of turkeys had died.
It was the first case of the virus in domestic farm birds in the European Union and threatened to deal a severe blow to France's struggling €6- a-year billion poultry industry the biggest in the EU.
Poultry sales in France are already down by about 30 per cent and Japan has suspended all poultry imports from France.
Mr Chirac reiterated it was safe to eat cooked poultry after meeting farmers and vets at an annual agriculture show in Paris, where no poultry are on display this year because of safety concerns.
"Unfortunately you can see a completely unjustified sort of total panic developing," Mr Chirac said. "There is no danger in eating poultry."
Bird flu was discovered on Thursday at a farm with 11,000 turkeys in the Ain department, a region where two cases of H5N1 had already been confirmed in wild ducks.
Laboratory tests by Afssa, France's national agency for nutritional safety, showed the virus found at the turkey farm was 99 per cent identical to that found in one of the ducks, the Agriculture Ministry said in a statement.
An investigation was under way to establish how the farm became contaminated with the virus, the ministry added.
"What worries us, and this is why we have reacted immediately, is that the farm is within the protection zone that we set up for the first duck," Agriculture Minister Dominique Bussereau said.