Like-for-like sales, which strip out the impact of new stores, fell by 2.8 per cent in the UK between April and June, with total group sales falling 0.7 per cent reports The BBC.
Like-for-like sales at the UK food business rose 0.6%.
The company also announced the departure of the head of general merchandise, Kate Bostock.
She will be replaced by John Dixon, who currently heads the retailer’s food business, on 1 October. Mr Dixon will be replaced by Steve Rowe, currently director of retail.
“Our food business has again performed strongly,” said M&S chief executive Marc Bolland.
“General merchandise underperformed in a difficult trading season. We are confident we are taking the necessary steps to address this.”
The company said clothing sales had been affected by the stock issues that first hit sales in the first three months of the year. In April, M&S admitted to running out of stock in some of its best-selling lines of womenswear.
The retailer said it had “improved our buying and merchandising” to bring stock back on target for its autumn/winter collections, which will be launched later this month.
It also said the wet weather had affected the wider clothing industry.
Analysts said M&S had been hit particularly hard.
“While all retailers with seasonal lines are at risk from dramatically unseasonal weather, Marks have suffered more than most,” said John Ibbotson at Retail Vision.
“Only their food department stayed afloat amid a deluge of bad numbers. SOS M&S – that’s the inescapable conclusion to be drawn.”
Outside the UK, the retailer performed better, with international sales rising 0.9 per cent.
“Our key international markets in India and China continued to trade strongly, with double digit growth,” the company said.
In May, M&S reported its first fall in annual profits for three years.
Pre-tax profits for the year to the end of March were £658m, down 16 per cent from the previous year’s £781m.
