PARIS (Reuters) - French supermarket chain Intermarche could be fined after competition investigators found it breached rules with its hefty discounts on products such as the Nutella chocolate spread offer that caused pandemonium in some stores last month.

The French government’s DGCCRF competition and anti-fraud agency found that Intermarche broke a French law forbidding retailers from selling products below their actual cost, junior economy minister Delphine Geny-Stephann said on Thursday.

Intermarche’s discounting in this case risked a potential fine, Geny-Stephann told RTL radio.

Under French law, a judge will now consider the case and decide whether to impose a fine, which can be up to 375,000 euros ($461,000) for selling at a loss.

Intermarche had no immediate comment on Thursday.

French retailers are only allowed to sell below cost during annual sale periods on products they have had in stock for at least 30 days.

In an interview with newspaper Le Journal du Dimanche this month, Intermarche Chairman Thierry Cotillard said that the price offer was made during its official winter sales period.

The promotions at the end of January offered 70 percent reductions on some grocery brands and led to scuffles among shoppers trying to grab jars of Nutella.

Nutella, made by Italian group Ferrero, is a household favorite in France and footage of the unrest in the Intermarche stores went viral on French social media.

The promotions also covered Procter & Gamble's PG.N nappy brand Pampers, Nestle's NESN.S Perrier sparkling water and Lavazza's Carte Noire coffee, the DGCCRF said.

The promotional offer was annoying to the French government as ministers were preparing to unveil draft legislation aimed at ensuring fairer prices for farmers, notably by curbing aggressive discounting by supermarkets.

The planned food law has been advocated by President Emmanuel Macron as a key response to the long-standing difficulties of many French farmers.

Macron hosted hundreds of young farmers at a reception at the Elysee presidential palace on Thursday, ahead of the annual Paris farm show -- traditionally a politically important event in France -- a day after farmers staged protests against trade concessions to South American countries.