British high street mainstay Marks & Spencer on Wednesday announced an unexpectedly deep slump in clothing sales over the Christmas period. The retailer suffered a 3.8 percent fall in sales of non-food items in the 13 weeks up until December 29, leading to a worse-than-expected 1.8 percent fall in overall like-for-like sales. Chief Executive Marc Bolland admitted in a statement that the non-food sales results were \"not yet satisfactory\". He added that measures being taken by the new management team \"will address\" the weak figures. \"Our plan is to transform Marks & Spencer from a traditional UK retailer to an international multichannel retailer. We are making good progress against this plan,\" he explained.