Carrefour China apologized again to the public Tuesday and promised to introduce public supervision of prices after consumer authorities blacklisted it for cheating on prices last week.

It was the company's second apology since Jan. 26, when the National Development and Reform Commission, China's top economic planner, criticized the Carrefour and Wal-Mart chains for overcharging.

Five Carrefour stores in Shanghai and southwest China's Yunnan Province were fined 500,000 yuan (75,988 U.S. dollars) each on Jan. 29 for overcharging.

Carrefour China said in a letter mailed to news organizations and posted on its website Tuesday that it had launched price inspections in all outlets nationwide, and had already covered more than 8 million price tags.

The company said it would fulfill its promise to refund customers five times the difference between the price charged and that on the label, and would welcome public monitoring of pricing.

Carrefour pledged to keep routine supervision of price labels.