British high street retailer Marks & Spencer announced on Thursday that sales rose in the fourth quarter of its financial year, despite challenging conditions on the high street. Group sales increased by 3.1 percent in the 13 weeks to March 30, compared with the equivalent period of the company\'s previous fiscal year, M&S said in a trading update. British like-for-like sales, stripping out the impact of new floor space, climbed 0.6 percent in the same period. General merchandise sales sank 3.8 percent but food sales grew 4.0 percent. \"We are working hard on improving our performance in general merchandise and, despite difficult trading conditions, we made progress in our operational execution,\" said chief executive Marc Bolland in the statement. He added: \"We delivered an excellent result in food, with performance well ahead of the market, as customers continued to trust us for provenance and quality.\" The update was well received by investors, who sent the group\'s share price to the top of London\'s FTSE 100 index. In morning deals, shares jumped 3.22 percent to 396.15 pence on the FTSE, which was up 0.08 percent at 6,392.22 points. However, the update also revealed that M&S clothing sales remained under pressure as a result of cold weather and weak consumer confidence in Britain. That forced M&S to increase its promotional activity last month. \"The M&S figures confirm our suspicions that things would get worse before they get better,\" said Bryan Roberts, director of retail insights at consultancy Kantar Retail. \"While food continues its robust performance driven by some great innovation, the slump in fashion sales remains worryingly entrenched. \"While the weather hasn\'t helped, our concerns persist that M&S lacks a coherent understanding of who its target shopper is and what they need to deliver to capture spending.\" M&S, which sells clothes, food and homeware, was founded in 1884 and was once one of the world\'s most profitable retailing companies. However, it has struggled from poor clothing sales in recent years. Back in January, M&S had announced an unexpectedly deep slump in clothing sales during the critical Christmas trading period in 2012.