Sales at department store chain John Lewis fell 3.8% last week, partly the result of a calendar effect because of this year’s later Easter and Mothers’ Day.

Turnover was £54.4m in the period to March 26, when sales at the Oxford Street branch were disrupted by protests in central London last weekend and fell 11.3%.

Fashion sales fell 7.6% and the home category was down 6.5%. Warm weather affected footfall for both. Sales of electrical and home technology rose 5.9% however, helped by the launches of the iPad2 and Nintendo Dsi 3D.

Online sales rose 17.5%. Peter Jones in London and the Aberdeen shop were the only established stores to end the week in positive territory.

John Lewis buying director, home, Paula Nickolds said: “As we enter our third trading period, we clearly need to deliver our best possible results.

“There are lots of opportunities ahead from Mothers’ Day, Easter and the royal wedding, and we should be confident that we can offer both the product and shopping experience to excite our customers during the crucial few weeks ahead.”

Sales at grocery chain Waitrose climbed 6.8% over the week to £99.3m. A £10 dinner for two meal deal proved popular and online flower orders rose 23% year-on-year ahead of Mothers’ Day.

Total orders on the recently revamped Waitrose.com leaped 31% year-on-year.