Wal-Mart, the world’s largest retailer, says the new small Marketside grocery stores it is to launch this autumn could expand to a chain of more than 1,000 stores, delivering $10bn-plus in annual sales.

The retailer plans to open 10 of the 15,000 sq ft Marketside stores initially, including four in the Phoenix area, where they will be competing directly with Tesco’s recently launched US Fresh & Easy store concept.