LONDON (Reuters) - J Sainsbury delivered the strongest growth among Britain's so-called Big Four grocers in the 12 weeks to April 14 and was the only one to increase market share, monthly industry data showed on Tuesday.
Market researcher Kantar Worldpanel said sales at Sainsbury, Britain's third-largest grocer, grew 5.4 percent in the period, increasing its market share to 16.9 percent.
Kantar said a feature of the period was an increasingly polarised grocery market, with the upmarket Waitrose, which is owned by John Lewis, as well as discounters Aldi and Lidl, all posting record market shares of 4.9 percent, 3.4 percent and 3.0 percent respectively.
"Pressure on household budgets is undoubtedly driving some of the growth at the discounters, but messages about quality are starting to resonate," said Edward Garner, director at Kantar Worldpanel.
"Shoppers rate Waitrose highly in terms of provenance and clearly-defined supply chains - important credentials in the wake of the horsemeat scandal and factors which have clearly boosted sales at the retailer," Garner added.
Sales at market leader Tesco rose 1.0 percent and were up 3.0 percent at No. 2 player Asda, the British arm of Wal-Mart, while sales increased 0.3 percent at No. 4 grocer Wm Morrison Supermarkets - outcomes all below overall market growth of 3.6 percent.
Last month Sainsbury posted higher-than-expected fourth-quarter sales, while last week Tesco announced a 51.5 percent slump in yearly profit.
Kantar said grocery inflation was 3.8 percent for the 12 week period.
(Reporting by James Davey; Editing by David Holmes)