Marks and Spencer has blamed unusually warm weather in October and November for poor results across its clothing line, which saw its 14th consecutive quarterly fall.
M&S said its like-for-like general merchandise sales, which is mainly clothing, fell 5.8% in the third quarter.
M&S chief executive Marc Bolland said the company had a "difficult quarter in general merchandise thanks to unseasonal mild weather.
"We deliberately held back the level of discounting especially in December. While this had an adverse impact on sales we delivered a good performance on gross margin," said Bolland.
M&S also reported that sales on its revamped website were down 2.7%, thanks in part to a disruption in December at the Castle Donington online sales distribution centre.
Food sales were up 17% in the Christmas week as the retailer sold record numbers of turkeys, desserts and party food.
"M&S had a very good Christmas in food. We delivered record Christmas sales, strongly outperforming the market," said Bolland.