Marks & Spencer (MAKSY)  shares rose to the top of the FTSE 100 leaderboard Thursday after the retailer said group sales rose 4.3% in its fiscal third quarter and cautioned that uncertain consumer confidence would hit the company's earnings in the following three-month period. 

Overall group sales rose 5.9% in the 13 weeks ending on Dec. 31, the company said, but that figure slips to 4.3% owing to the steep decline in the pound on foreign exchange markets. Food sales rose 5.6%, but were only up 0.6% on a like-for-like basis, which matches sales from stores which have been trading, or where there has been no significant change in footage, for at least 52 weeks.

Christmas sales in the company's Clothing and Home divisions grew 2.3% on a like-for-like basis, M&S said, well ahead of the 0.3% gain forecast by analysts polled by Reuters. M&S said around half of the overall 3.1% gain in Clothing & Home was due to "the inclusion of five additional days of the December sale."

M&S shares gained 2.3% to change hands at closed at 347.55 pence each by 08:30 GMT, nearly matching the 2.74% gain recorded over the past three months. That performance, however, has lagged the 5.55% advance for the FTSE 350 Food & Drug Retailers Index.

"I am pleased with the customer response we have seen to the changes we are making in line with our plan for the business. I would like to thank the whole team for their hard work over this busy period," said CEO Steve Rowe. "In Clothing & Home, better ranges, better availability and better prices helped to improve our performance in a difficult marketplace. We also continued to substantially reduce discounting, including over Black Friday."

"As we look forward, our Q4 reported numbers will be adversely affected by sale timing and a later Easter. Against the background of uncertain consumer confidence the business remains focused on delivering the strategic actions announced last year," Rowe added.