UK retailer Morrisons lost ground to its bigger rivals Asda and Sainsbury’s, Kantar Worldpanel claimed today (11 September) as they issued their latest sales data on the country’s grocery sector.

The UK’s fourth largest grocer saw its market share drop to 11.5% in the 12 weeks to 2 September, from 11.7% a year earlier, Kantar revealed.

“The pressure on Morrisons continues. However, this is to some extent inevitable, as the retailer presently offers no online ordering and currently only a small number of ‘M Local’ convenience outlets – two areas which are currently major contributors to the growth of its three main competitors,” said Kantar director Edward Garner.

In contrast, Asda saw its market share rise to 17.6% from 17.4% a year earlier, when excluding its Netto acquisition. Sainsbury’s share rose to 16.4% from 16.3% last year.

Kantar said the big winners were outside the “big four”, with successes at the two opposite ends of the industry as Waitrose and discounter Aldi held on to record share and growth.

Waitrose, which is owned by the John Lewis Partnership, grew its market share to 4.6% from 4.4% thanks to growth of 7.8% – outperforming the market average of 3.3% growth.

Outside of the big four, however, Aldi remains the “star performer”, Kantar said, holding on to its “all-time record share” with growth of 26.6%.

The discount retailer’s market share leap to 2.9% from 2.4% a year earlier, with growth driven mainly by “dramatic” growth in spend levels of existing customers – up 36% over the past two years – rather than an increased number of shoppers, Kantar said.

Grocery inflation was 2.9% in the period, continuing the downward trend from the recent peak of 6.2% for November 2011.