Aldi sold nearly £1bn of goods in the UK last month, with sales buoyed by rising demand for its premium ranges.
The German group’s British division, the country’s fifth-largest grocer, said the week beginning 17 December was the busiest in its history, with sales up 10% on last year.
Traditionally, shoppers opt for quality over low prices during the festive period, but Aldi, Lidl, Iceland and other discounters have increased their luxury ranges, piling further pressure on their bigger rivals.
The true impact of the cut-price chains on traditional supermarkets over the Christmas period will become clearer this week, with UK grocery market share figures published on Tuesday, along with a Morrisons trading update. Sainsbury’s, Tesco, Waitrose and Marks & Spencer are also all due to report on their Christmas performance this week.
Aldi said its sales performance reflected a surge in demand for its premium ranges, such as beef chateaubriand, 32-year-old French brandy and panettone.
“We begin the new year with great momentum as the UK’s fastest-growing supermarket and on the back of record Christmas sales,” said the chief executive, Giles Hurley.
Analysts said Aldi’s sales were bolstered by an 8.5% increase in space at the chain, which opened 65 stores last year, and the retailer was likely to have been disappointed by sales growth at established stores.
Aldi has 827 stores in the UK and plans to open 70 more this year, as it aims for a goal of 1,200 shops in Britain by the end of 2025.
Thomas Brereton, a retail analyst at GlobalData, said: “Although the headline numbers shout success, the tide may slowly be turning on Aldi’s triumphant march of growth.
“The retailer has only unveiled its results for the final week before Christmas, and while certainly a crucial period, hints at slightly weaker growth throughout the rest of the month.”
Aldi, Lidl and other discount chains such as B&M and Home Bargains have been grabbing market share from traditional grocers in recent years and forcing them to cut prices on everyday items in order to cling on to shoppers.
Morrisons said on Monday it will slash the price of more than 900 products, cutting as much as 20% off “store cupboard favourites” such as tinned tomatoes, cereal, sandwich fillers, ready meals and multivitamins.
Tesco also said it would cut prices on hundreds of items including PG Tips and Cathedral City cheddar.
Aldi said it would look at Morrisons’ price changes, but said it was confident that its stores “would still be cheaper to shop in”.
“We see this every January, and Morrisons is unlikely to be the last one to cut some specially chosen prices,” a spokesman said.