The French Government bowed to a public outcry over mad cow disease yesterday and, in a series of measures, banned T-bone steaks and all use of meat-and-bone livestock feed. 

The moratorium on animal-based feed for all livestock amounted to a climbdown for Lionel Jospin, the Prime Minister, as the panic over BSE led to a boycott of beef. 

In the view of the Socialist-led Government, President Chirac fanned fears for political purposes last week when, without consulting Jospin, he issued an alarmist call for an immediate feed ban. 

Jospin had earlier insisted on awaiting scientific advice at the end of the year on the merits of a move that, among European Union states, has so far been applied only by Britain. 

The Prime Minister, who has been dueling publicly with Chirac over beef, has been criticized for failing to respond more swiftly to a crisis of public confidence. Animal feed, allowed until yesterday for pigs, poultry and other livestock, is blamed for spreading BSE across France, which has Europe s biggest cattle herd. 

The disease was imported from Britain in the late 1980s. Experts are unanimous that, due to lax enforcement of a 1990 ban, meat-and-bone meal has continued to be fed to cows, both accidentally and fraudulently. 

Three more BSE cases were reported yesterday, bringing the French total this year to 99 and the total since 1998 to 180. 

Jospin called the feed measure a "further step in protection," but insisted that "there is no scientific proof that suggests that eating beef or drinking milk poses a risk to health." 

Although cattle with BSE are still entering the food chain in France, the removal of "risk tissue" is held to be a guarantee against variant Creutzfeldt-Jakob disease (CJD), the human equivalent of BSE. Three cases of CJD have been identified in France. 

Among other steps, the sale of T-bone steak will be outlawed on the advice of the national Food Safety Agency because of the risk that it carries infective material from the animal s spinal cord. To eliminate this risk, butchers will also be ordered to provide a new cut of côte de boeuf, a traditional French dish. 

In further attempts to calm fears and improve safety, random tests will be carried out on cattle carcasses at slaughterhouses and the Government will review steps to eliminate certain cattle from the food chain. 

Unlike Britain, which allows consumption only of animals younger than 30 months, France has no age restrictions on cattle entering the food chain. The Government has rejected an offer by the FNSEA, the main farmers union, to halt the sale of cattle born before 1996, the year that British beef was banned and tighter restrictions were imposed on animal feed. 

The union welcomed the government action yesterday as a measure to quell the "hysteria" now afflicting France, but said that there was no scientific reason for doing so. "We are in a completely irrational area, but if it reassures consumers, so much the better," Luc Guyau, the union leader, said. The move was, however, welcomed by José Bové, the leader of the militant small-farmers movement. 

Beef sales have slumped by more than 40 per cent over the past ten days as consumers have boycotted butchers, supermarkets and hamburger and steak restaurants. School canteens in Paris and dozens of towns have removed beef from their menus. 

The Government decision on feed, depicted as temporary, will mean stocking a million tons of unused animal-based feed. This will cost tens of millions of dollars and raise the risks, already faced by Britain, of environmental damage. The switch to vegetable-based feed for all French livestock will mean a big demand for soya-bean and rapeseed, much of which will have to be imported. France is also worried that imported soya-based feed could contain genetically modified material.