Asda has ploughed money into its digital operations while throwing its weight behind a sustained low-price strategy amid a grocery market awash with promotions.

Asda chief executive Andy Clarke pledged “unwavering commitment to deliver everyday low prices for customers” as money-off coupons continue to dominate grocery sector promotions.

The Walmart-owned grocer today reported a 1.3% increase in like-for-like sales in the first quarter to April 14.

Clarke said: “This represents a strong performance in what remains a very tough market.

Clarke said: “Low prices are who we are and are what drive real loyalty. They are not just a gimmick or an unsustainable or knee-jerk promotion.”

“We have continued to achieve growth on growth by lowering the prices of essentials and investing in technology to make shopping more convenient.”

Asda launched its Price Lock initiative in March, pledging to keep the price of staples low after a £100m investment. The scheme complements its Price Guarantee commitment to be 10% cheaper than Tesco, Sainsbury’s, Waitrose and Morrisons.

Morrisons chief executive Dalton Philips said last week that the grocery market is “as competitive as it’s ever been” when he reported a 1.8% fall in first quarter like-for-likes.

Asda’s online sales rose 16% in the first quarter. The grocer said it is leveraging “revolutionary” Walmart technology including Scan and Go, which it is piloting “in a number of stores over the next few months”.

Walmart offers the service in 70 stores in the US. It allows shoppers to scan items on their iPhone or iPad in the aisles and pay for them at a self-checkout counter.

Asda has also rolled out its hybrid checkouts to 20% of its 568 stores. The tills, which are used to cut queues, can be switched from checkouts operated by a member of staff to self-service scanners, meaning they are always open.

Asda recently disclosed plans to invest £700m in digital initiatives and building new stores in 2013.