The retail giant Carrefour SA made an official apology on Wednesday after 11 of its stores in China were found to have overcharged consumers with false pricing.

The French retail company also said it will establish an internal group to enhance pricing control.

Chen Bo, spokesperson from Carrefour China, said in a statement that Carrefour "sincerely apologizes" for causing losses to the customers and promised to refund 5 times the difference.

"We will establish a special control group to further conduct internal price quality inspections with wider coverage and higher frequency," said Chen, noting that the company will cooperate with local price inspection and supervisory bodies and involve them to provide special training on price quality control to related staff and managers.

Carrefour's announcement came shortly after China's National Development and Reform Commission (NDRC) said Wednesday it found deceptive pricing practices during a national inspection at certain supermarket stores, including 11 stores of Carrefour SA and 3 stores of Wal-Mart Stores Inc.

NDRC also ordered local authorities to fine the supermarket involved five times the overcharged amount or up to 500,000 yuan ($97,197) if the amount cannot be calculated, according to the statement.

Chen Zhijiang, an official at NDRC, told China National Radio that in all the cities they investigated, Carrefour stores were suspected of price cheating.

The investigation is part of the government's efforts to curb inflation as the Chinese Spring Festival nears.

"We will urge Carrefour to check all the stores and protect consumers' interests," the report quoted Chen as saying.

According to the report, the investigated cities are mainly provincial capitals including Tianjin, Shanghai, Wuhan, Shenyang.

Regulators selected 30 to 40 items at random and compared their label prices with selling prices, and there were always three or four items that were not consistent.

Zhang Xuejing, senior public relations manager at Wal-Mart China, said Wal-Mart attaches importance to price checking and insist on internal inspection and label management.

"Every week, there are 700 price supervisors to check more than 1 million items," Zhang said, "We will seriously punish whoever is responsible for such acts."

Zhang also said that the company offers discounts on more than 10,000 high-quality products to customers.

The NDRC said on Wednesday that all supermarkets in China should avoid overcharging customers, adding that it will further strengthen price monitoring over the Lunar New Year period.

According to the National Bureau of Statistics, China's GDP grew 9.8 percent in the fourth quarter from a year earlier, faster than the third quarter's 9.6 percent increase.

The country's consumer price index hit 4.6 percent in December, down from November's 5.1 percent, which was a two-year high.