Retailer Marks & Spencer has posted its worst underlying quarterly sales performance for three and a half years.

It said its womenswear trade was ravaged by wet weather in April and June.

The firm, which sells clothes and and homewares as well as food, also said that the head of its non-food business Kate Bostock would leave the business.

She adds her name to a list of significant top management departures this year. Bostock will leave M&S in October. Her job will be taken by John Dixon, the current boss of food.

Marks & Spencer said sales at UK stores open more than a year fell 2.8% in the 13 weeks to June 30, its fiscal first quarter. That was the firm's worst quarterly drop in sales since the third quarter of the 2008/09 financial year.

The outcome compared with analysts' consensus forecast of a fall of 3%, and a decline of 0.7% in the fourth quarter of the previous year when the retailer erred by running out of best-selling women's knitwear and footwear lines.

The company's like-for-like general merchandise sales, spanning clothing, footwear and homewares, fell 6.8% compared with analysts' consensus forecast of down 6.7%.

''General merchandise underperformed in a difficult trading season. We are confident we are taking the necessary steps to address this," said chief executive Marc Bolland.

Food sales on the same basis rose 0.6% versus analysts' consensus forecast of a rise of 0.8%.

M&S said its key international markets in India and China continued to trade strongly with double digit growth.

But it said that sales were impacted by currency translation of euro denominated countries as well as continued macro-economic weakness in Ireland and Greece and the on-going restructuring of its Central European business.