Aldi has joined the flurry of retailers launching big promotions or press ad campaigns in the wake of Asda's headline-grabbing 10% Price Guarantee.

Swap & Save would save shoppers more than 40% on their usual shopping, it claimed in press ads urging shoppers to 'Try the Aldi challenge today and see how much you can save!'.

The campaign, launched this week, centres around the savings on offer "without compromising on quality" when shoppers replace branded products at Tesco, Asda and Sainsbury's with Aldi's exclusive brands.

The ads compare the prices of a range of 15 staple brands including PG Tips, Heinz Baked Beanz, Del Monte orange juice and Fairy liquid. At Tesco, Asda and Sainsbury's, the average basket price was £23.94, claimed Aldi. Aldi alternatives cost a total of £13.32, representing a saving of more than 40%.

The move is Aldi's first swap and save campaign and a tactical departure from simply highlighting its low prices and 'Never Ending Discounts'.

Aldi would not comment on whether the promotion had been prompted by Asda's 10% Price Guarantee or high-profile press campaigns from other major retailers including Tesco and Morrisons.