The law will ensure there are no repeats of scenes last year when Intermarché surprised everyone with a 70% discount on Nutella – and caused violent riots in several supermarkets.
Under the new law, which is set to come into force on March 1, supermarkets can no longer offer discounts of more than 34% off the price of food.
The law also rules that supermarkets cannot re-sell any food items for less than a 10% margin on the base cost.
Relèvement du seuil de revente à perte (raising the threshold for selling at a loss) aims to ensure that farmers and other producers are fairly paid.
Super-promotions are still allowed on cosmetics and household products, such as cleaning materials, shampoos and shower gels. Reductions on food are expected to stay between 20% and 30%.
The best deals on offer will be “buy two, get a third one free” but the word “free” will not be allowed in advertising.
No more than 25% of a supermarkets’ annual turnover can come from discounted products.
The stores warn that, as a result, the price of 3,000 products could increase by 1%.
Big discounts bring in around €1billion every year, say supermarkets. Leclerc has already responded by reducing the price of 4,600 items in its own-brand Marque Repère range, as this is not considered to be a resale of produce.
Lidl marketing director Michel Biero claimed offers could be made in other ways, such as loyalty cards.
He said: “Offering 70% off a product or giving the same value of credit on a loyalty card is the same thing for the consumer: one is forbidden but the other is not.”