Upscale department store group Harvey Nichols on Monday admitted sales at its London outlets, including its famous Knightsbridge outlet, have remained flat in the first 15 weeks of the year. But the firm, which posted a 20 per cent slide in annual profits last month and will open a new store in Edinburgh this autumn, revealed that sales at its Leeds store are up 11 per cent over the period and it is "cautiously optimistic" about the future.