Morrisons has booted Asda from its customary top spot, undercutting it by just 32p with the help of a joint of unsmoked gammon.

Morrisons was the only retailer to offer the unsmoked gammon joint for under £4.50/kg, at 82p/kg cheaper than Asda’s. It also began a promotion on Radox Herbal Bath, which was down 66p.

Surprisingly, there were no significant reductions at Asda. Promotions ended on soft scoop vanilla ice cream, which was up 20p and Cheestrings, up 14p. There was also a 52p hike on Stella Artois.

Tesco crept up a place to third, despite four promotions ending – Kettle Chips were up 55p, the large mango 69p, McCain Home Fries 14p and oranges 3p. A promotion began on Tetley tea bags, which were down £1.55, and there were reductions on the unsmoked gammon joint of 41p/kg and Heinz Cream of Tomato Soup of 15p.

There were no hikes at Sainsbury's but just three reductions and it slid a place to fourth. Oranges were down 3p, sausage rolls down 7p and Tropicana 18p.

Waitrose’s trolley cost £10.91 more than Morrisons’. Two promotions ended, increasing the price of naan bread 48p and Patak’s korma sauce 55p. Pears were down 13p/kg and Stella Artois down £1.67 thanks to new promotions.