Shares in Big Four supermarket Sainsbury’s (LON:SBRY) are up 5 percent this morning, as the store reported a sales increase of 1.2 percent in the three months to Christmas.

The store’s market share increased by 0.2 percentage points year-on-year to 16.7 percent, according to market researcher Kantar Worldpanel. Fraser McKevitt, head of retail and consumer insight at Kantar said: “Consumers continue to be drawn to the retailer’s ‘Taste the Difference’ range, and with sales of champagne and sparkling wine up by a quarter it seems clear that the grocer is successfully tapping into demand for premium goods.”

Britain’s Big Four supermarkets have had a tough time of late, seeing falling sales as budget rivals such as Aldi and Lidl increasingly win over their market share. However, Sainsbury’s has continued to perform the best of the Big Four; Tesco and Asda have both seen sales figures fall around 3.4 percent over the last 12 weeks.

Shares in Sainsbury’s are currently up 4.64 percent at 247.90 pence per share. (1024GMT)