Walmart (WMT) - Get Report is throwing its weight behind its ailing U.K. division, conceding it wasn't fast enough to respond to low-cost rivals in Britain's fiercely-competitive market.

Walmart said it will ensure Asda, which has 630 locations across the U.K., leverages its parent's purchasing strength, allowing it to buy everything from refrigerators to own-brand products to real estate for a cheaper price driving down costs, Walmart's chief administration officer, Scott Price, told Reuters.

Walmart has been losing ground in the U.K. for some time and Asda is the worst performing division for the world's largest retailer.

Asda sales fell 1.9% to £4.3 billion ($5.3 billion) for the 12 weeks to Jan. 29, making it the only grocery store experience a decline. Asda saw its market share drop 0.6 percentage points to 15.6%, according to industry data from Kantar Worldpanel.

However, Asda's decline has started to slow, with Kantar noting the retailer managed to increase the number of shoppers visiting store compared to the same time period last year.

In Walmart's third-quarter earnings, released in November, Asda sales had decreased 5.8% an improvement from the 7.5% drop in the second quarter.

Walmart releases its fourth-quarter earnings on Feb. 21, analysts are forecasting a decline in sales of 2% to 3% in the quarter.

Asda is the U.K.'s No. 3 supermarket behind Tesco (TSCDY) and Sainsbury's (JSAIY) with Morrisons (MRWSY) rounding out the top four, together the group is known as the "Big Four".

The FTSE 350 Food & Drug Index has gained 6.22% in the past three months.

However, the Big Four has been under pressure from low-cost competitors Germany's Aldi and Lidl, both of which are privately owned.

Kantar Worldpanel data showed Aldi had jumped to the No. 5 position, will sales growing by 12.4% in the 12-week period to £1.7 billion and market share hitting 6.2%.

"One thing that maybe we would criticize ourselves for is that we didn't start the repositioning of the business sooner, that we didn't focus more on the leverage opportunities so that Asda was able to invest more aggressively in price," Price told Reuters.

The new strategy will allow Asda to stock Walmart brands "put an Asda brand on it that is equal to the national brand in the U.K. in terms of quality and sensory, but at a price that no one can match," Price said.

Walmart also installed a new CEO, Sean Clarke, at Asda last year in a further bid to boost the profitability of the division. Clarke was most recently chief executive of Walmart's China operations.

British supermarkets have been engaged in a fierce price war as discounters gain ground, although there are signs that could soon be coming to an end.

The 18% fall in the pound since the U.K. voted to leave the European Union last June has forced prices up. Grocery inflation now stands at 0.7% for the 12-week period, this marks the second period of inflation following 30 consecutive periods of deflation from September 2014 to December 2016. U.K. consumer prices accelerated at a 1.6% clip in December, data from the Office for National Statistics indicated.

In its most recent earnings release last month, Tesco vowed to keep pressure on suppliers to keep prices lower.

"While deflation has eased, the price of a typical basket remains nearly 7% cheaper than in September 2014. We will continue to do all that we can to ensure that we offer our customers the best possible prices," Tesco said in January.

Walmart stock closed at $68.02 in New York on Friday.