Wal-Mart Stores Inc. (WMT)’s Asda chain has overtaken J Sainsbury Plc (SBRY) in the U.K. market for own-label products, Chief Executive Officer Andy Clarke said today.

“For the first time in our history, our private-label market share is ahead” of Sainsbury, the executive said in a speech at the IGD conference in London. “And we’re only building on that momentum.”

The grocer revamped its mid-tier priced “Chosen By You” range last year, after 4,000 items including ready-made meals were tested by consumers before they reached shelves. The line is now the fastest-growing own-label range in the U.K., Clarke said. Asda’s private-label products also include the higher- priced “Extra Special” line and value-orientated “Smart Price” range.