Boss Steve Rowe - who took over from Dutchman Marc Bolland in April - will also consider swapping clothes for food in some stores

Marks & Spencer will shut 30 stores and close down clothing departments in 45 more over the next five years after profits plunged by 88 per cent.

Chief executive Steve Rowe - who took over from Dutchman Marc Bolland in April - has been forced to announce its biggest shake-up for years.

Up to 45 of the retailer's clothing stores will also be replaced by its more successful food halls.

Mr Rowe also outlined plans to shut 53 stores across 10 international markets - including 10 in China and seven in France, while pulling out of Belgium, Estonia, Hungary and Lithuania - putting around 2,100 jobs at risk.

Details of the restructure came as it said underlying pre-tax profits fell 18.6 per cent to £231.3 million in the six months to October 1, while bottom-line profits crashed 88.4 per cent to £25.1million - down from £216million a year ago.

The profits fall has been blamed on struggling clothing sales and a £200million injection into its pension fund.

The cuts announcement sparked an improvement in its share price - up 6p to £3.55 when the markets opened this morning.

The move comes amid reports that high street shops are closing at a rate of 15 a day, with fashion outlets particularly hard hit.

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Struggles: Its bottom-line profits for the six months to October 1 crashed 88.4 per cent to £25.1million - down from £216million a year ago and from £279million in 2014

Revamp: Marks & Spencer is set to close 30 stores and convert 45 more to food halls in its biggest shake up on the high street for years

Still trading: The Marks & Spencer 'penny bazaar' in Newcastle's Grainger Market in 1955 - but its clothing business is still faltering

Steve Rowe said: 'We have now completed a forensic review of our estate both in the UK and in our International markets.

'Over the next five years we will transform our UK estate with 60 fewer Clothing & Home stores, whilst continuing to increase the number of our Simply Food stores. In the future, we will have more inspiring stores in places where customers want to shop that complement our growing digital offer.

'Internationally, we propose to cease trading in ten loss making owned markets, but intend to continue to develop our presence through our strong franchise partners.

'These are tough decisions, but vital to building a future M&S that is simpler, more relevant, multi-channel and focused on delivering sustainable returns'.

The M&S closures – which also affect some stores overseas including a flagship outlet in Paris and others in China – are part of a major shift in policy to devote more floor space to its successful food ranges and build its website sales.

At the same time as closing some older high street stores, the company is opening another 200 of its smaller Simply Food outlets.

It is also embarking on a new approach to fashion, dropping catwalk fads in favour of classic designs and higher-quality fabrics.

Experts have said that M&S is 'giving in' rather than reforming its once hugely successful fashion range, especially amongst women.

Phil Dorrell, a partner at Retail Remedy retail consultants, said: 'It feels like, by closing stores and cutting jobs without an accompanying announcement on a new strategy, M&S are giving in. Or rather, they are still digging, but this time a trench to retreat in to.

'The only time that M&S should be allowed to use that spade again is if they start digging the foundations for a revived and renewed fashion offer'.

A consensus of City analysts expect like-for-like sales at the firm's general merchandising division, with includes clothing, to fall by 3.9 per cent in the second quarter.

In July, Marks & Spencer revealed that its clothing arm suffered its worst sales performance for more than a decade as it cut back on promotions amid a 'weak market', with like-for-like sales plummeting 8.9 per cent in the first three months of the year.

Mr Rowe - who took over from Dutchman Marc Bolland in April - is undertaking a wide-ranging overhaul of the business as he attempts to turn the retail giant around.

In August, Mr Rowe swung the axe on 525 jobs at the retailer's head office in a bid to cut costs. He later embarked on a major shake-up of staff pay in an effort to mitigate the impact of the National Living Wage.

It has also been reported that he is gearing up to shut dozens of its high street shops and phase out clothing sales at select stores as part of a major overhaul.

Kate Calvert, analyst at Investec, said: 'Steve Rowe will give part two of his strategic update on November 8. Having set his first priority as reviving clothing sales in May, he is due to come back to the ideal UK store estate in a multi-channel world, international, operations, and capital returns.

'We believe the market already anticipates action in all these areas and is likely to focus on weak trading and profit decline.'

Au revoir: The M&S closures will also affect some stores overseas including a flagship outlet in Paris on the Champs Elysees

Change of strategy: A warm September did not help winter clothes sales on the high street - and M&S could now replace clothing with food

Investec is pencilling in a 23% fall in half-year underlying pre-tax profits to £218 million.

Experts also expect the chief executive to reveal plans for the company's international arm, which has more than 450 stores, with many forecasting store closures as part of a major retreat.

Ms Calvert described Marks & Spencer's owned businesses in Ireland, Czech Republic and Greece in particular as the 'main drag' on the international business.

Marks & Spencer's better-performing food division is forecast to see growth flatline with Helal Miah, investment research analyst at The Share Centre, flagging that Christmas sales will be pivotal.

'Investors should appreciate that although impacted by price deflation, food sales are being helped by the launch of new food lines and the opening of more of the 'Simply Food' convenience stores, so the company will be pulling out all the stops to entice people in to buy their festive spread,' he said.

However, Mr Miah cautioned that the spectre of Brexit could emerge as a major cause of uncertainty and lead to lower economic growth, ultimately impacting consumer spending.

In July, Mr Rowe said that consumer confidence had weakened in the run-up to the EU referendum, adding: 'While it is too early to quantify the implications of Brexit, we are confident that our strategic priorities and the actions we are taking remain the right ones.'

He added shopper confidence remains 'fragile' after the Brexit decision, warning that Marks & Spencer is 'operating in uncertain times'.

Just this week Next, a fierce rival to M&S which has closed some under-performing stores, reported a dip in sales and warned next year will be tough.

The chain's chief executive Simon Wolfson said: 'The macro-economic backdrop doesn't look exciting. It is likely we will have another year with a difficult consumer environment.'

Sign of the times: Britain's biggest clothing chain will use Tuesday's half-year results to signal the closure of a raft of shops around the globe

Tom Gadsby, an analyst at the stockbroker Liberum, said: 'Major store closures are needed to help restore margins [at M&S]. Its extensive store base, once a source of strength, is becoming a burden.'

He added that a £334million increase in sales through the M&S website since 2012 had failed to make up for a fall of £568million in clothing and home sales over the same period.

'We find it unsustainable that the company should continue to pay for its store base in the face of declining sales and then pay again for the channel shift by paying to fulfil online orders,' he said.

'The inescapable conclusion is to close space.'

City analysts expect like-for-like sales at the firm's general merchandising division, with includes clothing, to fall by 3.9 per cent in the second quarter. Investec is predicting a 23 per cent fall in half-year underlying pre-tax profits to £218million.

Jonathan De Mello, of the retail property advisers Harper Dennis Hobbs, believes M&S could close one in five stores by 2020, but admits this will be difficult 'because it changes the fabric of the high street'.

There were 15 shop closures a day in the first half of 2016 and new openings fell to the lowest level for five years, according to the accountants PwC and the Local Data Company.

Some 206 fashion shops closed and 119 opened – a net decline of 87.