M&S’ chairman Archie Norman has admitted the retailer’s turnaround has “taken too long”.

Speaking to LBC’s Money podcast, Norman revealed M&S was more than a third of the way towards reaching the target it set out in 2016 and warned that it “could slip back” if executives don’t pay close enough attention.

Norman joined the retailer less than a year after then-chief executive Steve Rowe unveiled a five-year cost cutting programme and a shake up of its clothing and homeware lines.

“M&S has been in some ways the most intractable retail challenge of my career of turnarounds,” he said.

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The former Asda chief executive and chair, who is credited with rescuing the supermarket before its sale to US giant Walmart, said the grocer “was in a worse shape undoubetdly but roughly speaking M&S had suffered 25 years of drift until recently”.

“It’s been a big challenge,” he said.

“I think it’s taken too long. I’ve been [at the company] for five and a bit years. I wake up every day wondering ‘What the hell have I been doing?’”

“We need to maintain the spirit of the turnaround,” he added.

His comments come amid a huge revival for the retailer that has seen dozens of larger stores shuttered and others refurbished with a more targeted offering.

M&S has also overhauled its clothing ranges which has helped to attract a younger consumer.

“One of the things I always hear from people is ‘I love M&S I used to go shopping there with my mum’ and your heart sinks,” he said.

“That’s lovely, but it’s not what we want to be today. We absolutely want to be for the modern mainstream.

“We’re 30 to 40% of the way towards what we can be,” he concluded.

Last week, Norman revealed the retailer’s board was rethinking its fully-digital AGM approach after facing backlash from shareholders.

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