LONDON (Reuters) - Asda, the British arm of Walmart <WMT.N> that has agreed a takeover by rival Sainsbury's <SBRY.L>, was alone among the country's big four grocers in holding its market share in the latest 12-week period, industry data showed on Tuesday.
Asda's sales rose 1.5 percent in the 12 weeks to Dec. 2 and it maintained its UK grocery market share at 15.0 percent, market researcher Kantar Worldpanel said.
In contrast Sainsbury's sales slipped 0.2 percent and its share dipped to 16.0 percent from 16.4 percent a year ago.
Sainsbury's, Britain's second largest supermarket group, agreed a 7.3 billion pound takeover of Asda, the number three, in April, a combination that could overtake Tesco <TSCO.L> as Britain's biggest supermarket group.
The deal is currently being investigated by Britain's regulator, the Competition and Markets Authority, which is expected to publish its initial findings next month.
Sainsbury's shares were down 0.8 percent at 0915 GMT.
Tesco's sales declined 0.1 percent, while Morrisons' were up 0.5 percent.
Tesco's shares were down 1 percent, while Morrisons' were down 2 percent.
German-owned discounters Aldi [ALDIEI.UL] and Lidl continued to be the big winners with sales increases of 12.2 percent and 11.2 percent respectively, partly reflecting aggressive store opening programmes.
Kantar Worldpanel said overall UK grocery sales rose 2.0 percent over the 12-week period, its slowest rate since March 2017.
"Consumers are benefiting from falling inflation. It now stands at 1.6 percent – less than half the rate of inflation in December 2017, when it reached 3.6 percent – leading to a slowdown in the overall market," said Fraser McKevitt, head of retail and consumer insight at Kantar Worldpanel.
Prices are rising fastest in products such as cola, sparkling wine and dog food, while falling in fresh pork, ambient cooking sauces and fruit.
(Reporting by James Davey; Editing by Paul Sandle/Keith Weir)