Comparable sales growth was up 3.4 per cent in the three months to the end of March. This was helped by the early timing of Easter, but Asda said sales still grew by one per cent when adjusted for seasonal factors.
Net sales also expanded by 3.7pc, while its online grocery arm and George.com clothing business saw sales expand by 8.3pc and 21.9pc respectively.
The results were released as part of Wal-Mart's update to the United States market this afternoon, in which the company unveiled a 4.4 per cent rise in revenue to $122.7bn (£90.9bn) for the quarter.
"Through Q1, we again stepped up our commitment to everyday low prices with the launch of Rolled Back Staying Back, which now extends to 667 lines that customers buy the most".
"Whilst we are not complacent, we are positive about our growing momentum and excited by the opportunity that our proposed merger with Sainsbury's offers to accelerate our successful strategy and go further, faster", he added.
Commenting on Asda's proposed merger with Sainsbury's, Walmart's president and chief executive Doug McMillon said: "We were pleased with the response of our colleagues in the United Kingdom..."
"In the United Kingdom, we saw sequential improvement in the business as comp sales increased for the fourth consecutive quarter".
Asda took a hit on profits as it continues to bring down prices in an effort to stay competitive.
The chain has been leading a turnaround in an attempt to improve sales amid a long-running supermarket price war, triggered by the onslaught of German discount operators Aldi and Lidl.
Walmart-owned Asda is on course to merge with Sainsbury's in a £12 billion deal, which will allow it to further invest in lower prices.
The Competition and Markets Authority is scrutinising the deal and it is expected that scores of stores will have to be offloaded as part of the competition review.
Asda has also been cutting jobs in the United Kingdom, including at its head office in Leeds, as part of a sweeping cost-cutting programme.
Asda's improved performance reflects moves by Mr Burnley to re-establish Asda's competitiveness by lowering prices, improving the availability and quality of its food and making its stores more attractive to shoppers.