Asda underperforms rivals in last three months - Kantar Worldpanel

A shopper walks past milk cartons in an aisle of Asda supermarket in London, August 17, 2015. REUTERS/Neil Hall -

LONDON (Reuters) - Sales at Asda, the British subsidiary of Wal-Mart , fell faster than at any of its "big four" supermarket rivals during the past three months, industry data showed on Tuesday. Market researcher Kantar Worldpanel said Asda's sales fell 3.0 percent in the 12 weeks to Oct. 11, with its market share falling 0.7 percentage points year-on-year to 16.6 percent. In August, Asda Chief Executive Andy Clarke described a slump in second-quarter sales as a "nadir" but there has been little improvement since. On Monday, Asda said it would accelerate investment in larger stores and put expansion on hold elsewhere as it seeks to improve trading. Britain's big four supermarkets - market leader Tesco , Asda, Sainsbury's and Morrisons - have been hurt by a price war as they try to stem the loss of shoppers to discounters Aldi and Lidl, and the impact of commodity-led deflation. "With like-for-like grocery prices 1.7 percent lower than last year, the supermarket price war shows no signs of abating," said Fraser McKevitt, Kantar Worldpanel's head of retail and consumer insight. Falling prices reflect the impact of Aldi and Lidl and the market's competitive response, as well as deflation in major categories such as eggs, bread, butter and crisps. Kantar said the British grocery market grew 0.8 percent overall in the period. Kantar said Sainsbury's was the only big four supermarket to see sales grow in the 12-week period. Its sales rose 1.1 percent, though its market share was static at 16.1 percent. Sales at Tesco fell 1.7 percent and its market share dipped to 28.1 percent, while Morrisons' sales fell 1.0 percent with its market share falling to 10.8 percent. After a slowdown earlier this year, Aldi and Lidl both saw their rate of sales growth return to above 17 percent. (Reporting by James Davey; editing by David Clarke)