Sales at department store group John Lewis last week fell on last year as good weather kept shoppers out of stores, according to figures released today.

With a total sales increase of 4.3 per cent to £64.3 million for the week to September 8th 2012, a significant decrease in footfall is in stark contrast to the 10.4 per cent growth seen a year earlier.

However, online sales boosted performance, increasing 25 per cent year-on-year as the retailer continues to strengthen its e-commerce position.

Yesterday, the group announced results for its first half with profit growing nearly 60 per cent while online sales rose 40 per cent and now accounts for almost a quarter of total sales at the department store.

In spite of lower footfall, events helped boost interest in the brand as the final week of the Paralympic Games saw a strong week-on-week boost to London 2012 general merchandise, while John Lewis‘ ‘Celebrate Britain‘ range fared well, enticing tourists and domestic customers alike.

Fashion ranges also proved popular last week as the back-to-school offer saw a 12 per cent rise in overall sales year-on-year as schoolwear sales rose 10 per cent while the highly anticipated range by Brit designer Alice Temperley hit stores and exceeded expectations as customers sought a host of clothing from the ‘Somerset‘ collection.

Nat Wakely, John Lewis‘ Director of Selling Operations, Region A explained that last week saw additional launches that proved equally positive.

“On Home it was the official launch of ‘House‘ which also beat its target and is being fuelled by excellent availability across the range and again a thank you to all of the Partners who have executed the pop up shops and the windows in quick time across the estate.

“Talking of pop up shops, it was the first week of our trailblazing one in Exeter, which has generated great interest to date.

“Turning finally to EHT, Ed Connolly and the team saw the best of our Buying Directorate growth at +16 per cent year-on-year. It was led by communication technology but ably supported by white goods and in particular laundry at +17 per cent.

“Of course, some exciting new products look set to be released over the next few weeks. Watch this space!”

It has also been announced today that the retailer has launched an ad campaign aimed at reinforcing its commitment to the ‘Never Knowingly Undersold‘ promise.

The ad will feature Brit musician Paloma Faith covering the INXS track ‘Never Tear Us Apart‘ while the TV advert which will debut tomorrow during X Factor takes viewers to the 1920‘s and present day under the tagline ‘What‘s important doesn‘t change‘.

Meanwhile, supermarket Waitrose reported an 8.4 per cent rise in total sales thanks to warm weather as sales of charcoal for barbecues increased by a massive 554 per cent on the same period last year.

Barbecue meat sales leapt 115 per cent while ice cream saw a 125 per cent lift over the week and suncare sales rose 144 per cent.

Tom Athron, Finance Director at Waitrose, commented on the results, saying: “Despite the warmer weather, ready meals continued the strong performance they have shown of late, with sales up 11 per cent as shoppers opted to spend time watching the sporting climax of the summer.

“But autumn is definitely in the air, and bagged apples and apples in tray packs rose 35 and 30 per cent respectively, driven by the introduction of new season English varieties, including Worcester, Estival and Suffolk Pinks.”