Tesco scored its first victory in The Grocer 33 this month, with Sainsbury displaced from its lead last week and Asda pushed into second place two weeks on the trot.

Asda had come in cheapest in seven of the previous nine surveys, but the country's number one supermarket defeated it by delivering a basket 37p cheaper at £45.13.

Asda came in at £45.50.

Asda and Tesco's prices were dead even on 26 of the 33 items, but Tesco was able to deliver the killer blow with, of all things, parsnips. A £0.99 per kilo promotional price on parsnips, down from the regular level of £1.88, created a price gap that Asda was unable to overcome.

Last week's winner Sainsbury dropped back to third place again this week with a total of £46.23 or 2.4% behind low price leader Asda.

Morrisons remained at last week's position of fourth.

However, Morrisons' total of £47.46 was 5.1% behind Tesco, a letdown from last week when Morrisons was just 2.7% behind the winner a week ago.

On a broader level, price parity increased slightly this week, as the price on 20 items on our shopping list was matched at four or more supermarkets, up from 19 last time.

Peering into the item level details, Asda, Morrisons and Sainsbury's this week all matched Tesco's 12.8% increase last week in the price of the 2-litre bottle of own label diet cola, taking it from £0.39 to £0.44.

Nestlé Shreddies was also in the spotlight, as Asda and Tesco returned the price of the product to £2.30 from a promotional price of £2.00. Somerfield inched its price on the same product up by 2p to £2.42.

Somerfield also put up the price of Andrex toilet paper by 10p to £1.99 and own label French baguettes by 2p to £0.47.

The latter added to a host of price increases in recent weeks on bread and bakery items at several supermarkets, driven by surges in the cost of both flour prices and energy costs.