Upmarket retailer Waitrose and discounter Aldi posted the strongest growth in the UK retail market during the 12 weeks to 17 March, the latest figures from Kantar Worldpanel revealed today (26 March).

According to the sales data, Aldi saw sales up 30.8% while Waitrose sales gained 12.5%, meaning each group achieved “record” market shares, Kantar said. The growth of the top and bottom end of the market demonstrate the continued polarisation of the UK grocery scene, Kantar suggested.

“Austerity and provenance are the key factors behind the varying retailer performances this month. Continued pressure on household budgets has helped Aldi, LIDL and Iceland to record market beating growths while Waitrose and Sainsbury’s have managed to mostly avoid adverse media coverage from the horsemeat scandal,” Kantar analyst Fraser McKevitt said.

Of the UK’s four largest multiples, Sainsbury’s booked the biggest gains. With year-on-year growth of 6.2%, McKevitt said the supermarket operator “firmly beat” the total market, which grew by 3.9%. “Since 2004, its annual share has been on a rising trend and now stands at 16.8% for the 52 weeks ending 17 March 2013,” he added.

Asda retained its market share of 17.9%, while Tesco and Morrisons both saw share eroded. Tesco stores dropped to 29.4% during the period, down from 30.2% last year, while Morrisons share fell to 11.7% from 12.3%.

However, moving forward Kantar highlighted the action both Tesco and Morrisons have taken to reverse declining trends. “Looking ahead, Tesco has responded with its Price Promise promotion which delivers coupons to shoppers at the tills and Morrisons has announced plans to plug its home-delivery gap during 2013. These strategies are expected to help boost the retailers’ performances going forward,” McKevitt said.

While the overall grocery market was in growth in the period, the rate was below the pace of inflation, which stood at 4.2%, as UK consumers continued to reduce basket size in response to higher prices and tough economic conditions.