Sales at Britain’s fourth largest supermarket, Morrisons, continued to grow over the Christmas period, sending shares up 4 percent at market open on Tuesday.

Sales of its premium products rose by 25 percent over the 10 weeks to the 7th January, with overall group like-for-like sales up 2.8 percent.

The group, who had been going through a difficult period and have implement a plan to better compete in the challenging supermarket environment, attributed this Christmas’ success to more tills, shorter queues and improved stock availability.

According to CEO David Potts, the group has “become more competitive, and despite the rising cost of many commodities the price of a basket of key Christmas items was the same as the previous year”.

“More and more customers found more things they wanted to buy at competitive prices at Morrisons this Christmas,” he concluded.

The latest figures from Kantar Worldpanel suggest all supermarkets had a better-than-expected Christmas period, with figures published on Tuesday showing that British shoppers spent £1 billion more in supermarkets over the last 12 weeks of last year than the year before.

Morrisons shares rose on the news at market open, before calming slightly to trade up 1.5 percent at 230.30 (1104GMT).