Both Aldi and Waitrose saw excellent sales performances in the latest 12-week data from Kantar Worldpanel, as the grocery market polarised.

Discounter Aldi posted a record market share of 3.5%, for the period to 12 May 2013, up from 2.8% last year, with year-on-year growth up 31.5% for the 12-week period - its highest rise.

Meanwhile, Waitrose held on to its record 4.9% market share, with growth of 12% - over three times the market average.

Lidl held on to its largest ever share of 3% and achieved sales growth of 8.9%.

Edward Garner, director at Kantar Worldpanel, said: “The success of Aldi, Lidl and Waitrose are clear examples of how shopping habits are divided across the country.

“We expect this growth to continue, particularly as store expansion plans open up the discounters to a wider number of customers,” added Garner. “This market polarisation also continues to pile the pressure on the big four grocers, with only Sainsbury’s beating the market and growing its market share this period.”

Grocery inflation stood at 3.9% for the 12-week period, matching market growth, which means pressure on households to trend down has lessened, according to Kantar.