Asda has been knocked off the top spot for the first time in three weeks by Morrisons, which undercut its nearest rival by just 26p to scoop the title of cheapest retailer.

Marking a double victory for Morrisons the week it unveiled strong interim results, its basket contained 22 of the 33 cheapest items on the Grocer 33 list. It also made four significant price cuts, reducing Stella Artois by 76p, Doritos by 42p, pineapples by 30p and fromage frais by 4p, though these were countered by the same number of price increases.

Asda slipped to second place even though its basket was 5.2% cheaper than last week and boasted seven price cuts. Pineapples were 70p cheaper than last week, pears 68p less, Doritos 48p less, McCain wedges 41p, sweet potatoes 40p and Green & Black’s chocolate and houmous 1p. It made only one price increase, on quiche lorraine, which was up 9p.

Sainsbury’s undercut Tesco’s basket by just 5p to take third spot. It made three significant price reductions. Carte Noir was down £1, balsamic vinegar 44p and Wall’s Magnum 1p. Its quiche lorraine was up 4p and its tuna 10p.

Tesco lagged behind in fourth place with a basket £3.23 more expensive than the cheapest retailer’s, even though it had 19 of the 33 cheapest items. The retailer made three significant price hikes – the peas were up 22p, McCain wedges up 18p and sweet potatoes up 50p. The fourth-placed retailer slashed the prices of six items. Croissants were 10p less than last week, pineapples 11p cheaper and quiche lorraine 17p, while Wall’s Magnum, Carte Noir and Green & Black’s chocolate were all down 1p.

It was business as usual for Waitrose, which made no price changes on last week. The fifth-place retailer’s items cost £10.46 more than Morrisons’.