Asda has revealed strong sales from the beginning of the year to April 20, as it continues to expand its grocery and non-food store estate.

The UK’s second-biggest grocer revealed a 6.4 per cent increase in like for likes, excluding petrol, for the three months to March 31. This is thought to be the first time parent Wal-Mart has broken out its figures publicly since acquiring Asda in 1999.

It is understood that Asda has been lobbying Wal-Mart for some time to be more open about its performance, which has improved significantly since 2005.

The Leeds-based grocer said its market share grew 0.3 per cent in the 12 weeks to April 20.

Asda president and chief executive Andy Bond said the results were “encouraging”. He added: “We have a duty to lock down inflation by working with our suppliers to cut costs, to ensure that our customers are always getting the best possible deal on their weekly shopping.”

Its performance was boosted by strong fresh food sales and a 30 per cent uplift in sales of its premium range, Extra Special.

Allegra Strategies project director Steve Gotham said: “Clearly, they are perceived as the most price-competitive of the leading supermarket chains and in the prevailing climate that plays to their strengths.”

Asda opened three food stores in the quarter and last month unveiled two more non-food Asda Living stores, bringing the total to 15.