The family shareholders of French retail giant Carrefour are reportedly putting pressure on the company’s executive chairman, Daniel Bernard, to make changes in order to improve the company’s performance.

“There is a growing impatience with management… Things are not moving fast enough,” a person close to the Halley and March families, who control around 16% of Carrefour’s shares and a quarter of the voting rights, told the Financial Times.

Shareholders have called for board changes that may include the departure of Joel Saveuse, the director in charge of Carrefour’s European operations, but Bernard has so far not made the desired changes, the person said.

Carrefour, the world’s second-largest retailer, has been underperforming, particularly in France, where its core hypermarkets have suffered amid intense competition and the rapid growth of discount retailers.