Marks & Spencer has unveiled a new marketing tagline – “Quality worth every penny” – to emphasise its value credentials and reputation for quality.

Marks & Spencer executive director Steven Sharp said the slogan, coinciding with the retailer’s 125th anniversary celebrations, was a “unifying statement” that worked across clothing and general merchandise.

He said: “It really sums it up. It’s simple, true, relevant today and for the next 125 years.”

Sharp said that M&S’s May campaign – including a 60-second TV ad fronted by Twiggy which aired for the first time last night - was comparable in scale to a Christmas marketing push, but spend will be less because of factors such as falling media buying prices.

Sharp said the anniversary campaign was “not just a trip down memory lane”. He maintained: “We probably have the most powerful campaign in our 125-year history.”

The retailer will also emphasise its ethical stance with the use of the marketing slogan “Doing the right thing” – the same phrase under which the retailer’s 2020 change programme has been formulated.