Discount duo Aldi and Lidl powered ahead of the market in October as the battle for Christmas sales kicked off.

Shoppers made an additional 14 million trips to the discounters during the 12 weeks to November 4, according to the latest data from Kantar Worldpanel.

Aldi grew sales 15.5% during the period, while rival Lidl’s revenues jumped 10.2%.

The Co-op emerged as the discounters’ closest competitor, registering a 5.1% uplift, while frozen food specialist Iceland enjoyed a 5% sales increase.

Asda outperformed the big four, Kantar data suggested, with sales advancing 2.6% across the 12-week period.

Morrisons and Tesco grew sales 1.5% and 0.4% respectively.

Sainsbury’s was the only member of the big four to suffer declining sales, as revenues went backwards 0.6% year-on-year.

Sales at Waitrose & Partners dipped 1% – the upmarket grocer’s first fall in sales since February 2009.

Fraser McKevitt, head of retail and consumer insight at Kantar Worldpanel, said: “Five years ago, just under half of British households were visiting one of the discount retailers at least once in a 12 week period. This now stands at almost two-thirds, which is reflected in their continued growth.”

Rival data from Nielsen also anointed Asda as the fastest growing member of the big four, with sales growth of 2.5%.

Sainsbury’s again lagged its mainstream rivals, suffering a 0.6% decline, while Tesco and Morrisons grew 0.3% and 1.2% respectively.

Nielsen data suggested Aldi and Lidl grew at a slower pace than Kantar figures suggested.

Aldi sales jumped 12.2%, while Lidl posted growth of 6.5%, Nielsen said.