Sales at John Lewis increased 11.4 per cent year on year in the week ending 10 November.
Electricals, home and technology sales soared 28.8 per cent during the week and sales of tablet devices and accessories surged ahead of last year, the department store says.
Christmas products, including themed menswear with reindeer motifs, are “selling well” while its in-store pop-up Christmas stores have “inspired customers to get in the mood for Christmas”, the retailer says.
Online sales have increased 37.5 per cent compared with the same week last year.
At Waitrose, sales increased 13.6 per cent during the week as shoppers started stocking up for Christmas.
Sales of festive products including Christmas crackers jumped 65 per cent on last year. Sales of sweets have increased 40 per cent and Christmas gift food sales increased 15 per cent compared to last year.
A festive promotion offering 25 per cent off wine has helped boost wine sales 38 per cent year on year.
Online sales at Waitrose.com have increased 61 per cent.
David Jones, Waitrose supply chain director, says: “With colder, darker days and festive television adverts upon us we can be in no doubt that the festive season is just around the corner. And, although customers might not be buying their fresh cranberries and sprouts just yet, the season of stocking up is certainly upon us and has been driving sales.”