John Lewis is to drop its “never knowingly undersold” price match pledge after almost 100 years, saying it has lost relevance at a time when it faces stiff competition from online only retailers.

The staff-owned department store chain said it had made the decision to retire the slogan this summer because its price promise did not apply to online-only retailers.

However, John Lewis said an increased in online shopping sales would allow it to invest £500m this year to lower prices to offer customers “everyday quality and value”.

That investment comes at time when consumers are facing a squeeze on disposable incomes as bills rise and pay growth fails to keep pace with inflation. It will also expand its Anyday cut-price range.

Under the never knowingly undersold slogan, which John Lewis introduced in 1925, the chain commits to refund customers the difference if they find the same item on sale elsewhere for a lower price within 28 days.

In a message to customers, Pippa Wicks, Executive Director of the brand, said: "I'm delighted to let you know that today we're announcing a £500 million investment so that we can bring John Lewis quality to you at great value prices, every day.

"As the cost of living rises, we have all become more conscious of our spending habits and with this new investment we will ensure that we are offering you the quality, style, service and trust that you expect, whatever your budget.

"With this in mind, we will be retiring our Never Knowingly Undersold policy this Summer.

"We recognise that this policy is no longer serving you in the way that we would like, as it doesn't allow us to match prices from online-only retailers.

"Due to the increase in online shopping, driven further by the events of the last two years, our £500million investment will ensure that all of our customers will benefit from fair and great value prices."

Martin Lewis, the founder of MoneySavingExpert, said the slogan change "won't have much practical impact for many.

He said:"The ‘never knowingly undersold’ promise has always been a bit of a psychological sop to consumers, giving an arguably false impression that John Lewis is cheap.

“In reality, it allows the store to charge what it likes and know that, for a few price-sensitive shoppers – less than 1% last year – who are bothered to check prices elsewhere after making a purchase, John Lewis will reduce its price but only to that of its high street competitors."