Half of the supermarket’s own brand price reductions were at least 10% including Waitrose shortbread fingers, 200g, Essential Vanilla Soft Scoop ice cream, two litres, and Essential smooth/crunchy peanut butter.

Some cuts, however, were much lower such as Essential British cooked cocktail sausages, 400g, cut by 4%, Essential salted and unsalted British butter, 250g, down 5% along with Essential reduced salt and sugar ketchup, 445g.

Waitrose said the cost-cutting round was part of a £100m investment to lower customers’ bills and the second time it has lowered hundreds of prices this year.

In February, the supermarket cut prices on more than 300 items.

But with food and non-alcoholic drink inflation rising to 19.1% in the year to April, the second highest rate in 45 years, shoppers’ budgets remain under pressure and experts say supermarkets should do more.

Waitrose move ‘positive’

Sue Davies, Which? head of food policy, said: “While Waitrose performed strongly for quality, range of products and store experience in Which?’s supermarket survey, it fell down on value for money. Our recent price analysis shows Waitrose continues to be the most expensive food shop. So while positive, this price cut alone is unlikely to be a silver bullet.

“Supermarkets must commit to doing all they can to help consumers during the cost-of-living crisis, including providing transparent pricing so shoppers can easily work out which products offer the best value.”

Aldi was ranked the cheapest supermarket for a basket of goods in May, its twelfth consecutive number one ranking in Which?’s supermarket study. Shoppers at the German discount store saved £18 on a basket of items compared to those shopping at Waitrose.

Asda scored top for a larger trolley of groceries, £31.59 cheaper than the equivalent shop at Waitrose.

Charlotte Di Cello, commercial director for Waitrose, said: “We’re investing millions in lowering the prices of everyday food across our aisles so customers benefit every time they shop with us.”

She added: “We’ll still react to any drops in food inflation and pass on savings to our customers as soon as the prices we pay begin to fall, and we’ll continue to pay farmers a fair price for their products too.”

Examples of price cuts on everyday and summer items

Product                                                                    Old Price          New Price        % Reduction

Waitrose Watermelon chunks 450g                  £5.00              £3.95                    21%

Waitrose Soft White Medium Loaf 800g          £1.15                £1.00                    13%

Essential British Pork Chops 400g                    £4.25               £3.75                    11%

Essential 10% Fat British Beef Mince 500g       £3.55               £3.15                     11%

Essential Smooth/Crunchy Peanut Butter       £2.35                £2.10                   10%

Essential Chicken Thighs 1kg                             £3.60                £3.25                  9%

Waitrose Valencia Ice Lollies                              £2.90                £2.75                   5%