The discounters enjoyed booming sales this Christmas, with shoppers seeking out premium-quality products at discount prices.

Champagne was the second-biggest seller at Lidl over the festive season, just behind semi-skimmed milk. Other top-selling products included smoked salmon.

Lidl discounted its Comte de Brismand Champagne from £12.99 to £9.99 over Christmas and new year. It has now sold out across the UK.

“We saw phenomenal sales of Champagne,” said a spokeswoman. “The sheer volume we sold was unprecedented and we are trying to restock across the country as quickly as we can.”

Although Lidl stopped short of revealing exact sales figures, it said its premium Deluxe range outperformed 2011 sales.

“We doubled the size of the Deluxe range at Christmas and sales increased by 200% from 2011 to 2012,” the spokeswoman said.

“We added items such as whole lobsters, scallops in Chablis sauce and caviar. We have had amazing feedback, so will definitely be doing it again.”

Lidl added that Nielsen data indicated the proportion of ABC1 consumers shopping at Lidl had risen from 25% to 41% since 2011.

The news came in the same week Kantar Worldpanel revealed the discount sector hit new heights in the run-up to Christmas.

Lidl grew sales by 10.8% and increased its market share to 2.8% in the 12 weeks to 23 December 2012. Aldi, meanwhile, posted sales growth of 30.1% and hit a record market share of 3.2%. By contrast, Sainsbury’s was the only big four supermarket to increase its market share.

“It’s a combination of Aldi and Lidl wishing to change the perception of their offer - and I think the customer perception is changing as well,” said Kantar Worldpanel director Edward Garner.

“If you go back in time they were regarded as weird and cheap, but over time they have been winning prizes for their products and Christmas is an ideal time to be offering premium products at a keen price point, like a goose for £34.99.”

Kantar also revealed Iceland hit a 12-year market share high of 2.2%.

Last October, Iceland chairman Malcolm Walker warned that like-for-like sales were down 0.2%. But speaking to The Grocer this week, he said business had “picked up no end” and he was more optimistic about full-year sales.

A spokesman added that Iceland’s like-for-like sales in November and December had showed an “improved trend”, up 1.5%. Total sales rose 5%.