The 129-year-old retailer will on Thursday report sales figures for the first three months of the year, which are likely to show a clear split in the high street business between its food and clothing operations.
City analysts have forecast that M&S will record a fall in like-for-like sales in general merchandise, which is primarily clothing, of up to 6pc, increasing the scrutiny on chief executive Marc Bolland.
The expected fall in clothing sales follows a 3.8pc drop during the key Christmas trading period as M&S lost market share to rivals such as Primark and Zara.
Analysts at Nomura, who predicted the sharp decline in Christmas sales, have forecast that like-for-like clothing sales will be down 6pc despite food sales increasing 3.5pc.
This would mean that total UK like-for-like sales in the fourth quarter fell 0.7pc and in the full-year by 1.3pc. This would be the worst annual sales performance since a 5.9pc drop in sales in 2009 under Mr Bolland’s predecessor, Sir Stuart Rose, when Britain was in a deep recession.
However, Mr Bolland and M&S also face concerns about the quality of their fashion ranges, particularly in womenswear.
Mr Bolland has overhauled the management of the division, bringing in John Dixon from M&S’s flourishing food business and Belinda Earl as style director. He is looking for the new team to drive an improvement in the company’s autumn and winter collection, which will be released later this year.
The M&S boss will point to these changes this week if the company comes under pressure from the City.
Mr Bolland is also likely to highlight the performance of M&S’s food business, whose sales are growing ahead of the grocery market. Food now accounts for 55pc of M&S’s sales and is a larger business than general merchandise, despite the fact that the company is the biggest clothing retailer in the UK.
Food sales in the fourth quarter will benefit from New Year’s Eve and Easter falling in the period when they did not last year. However, they will also reflect the popularity of M&S food for holidays and special events.
Jean Roche, analyst at Panmure Gordon, said: “We are positive on M&S’ strong brand, exposure to a wealthier customer, investment to improve its multichannel model, growing international business and the renewed strength of the food business.”