LONDON (Reuters) - Retailer John Lewis JLP.UL reported on Friday an 8.3 percent drop in weekly sales at its department stores, saying the turmoil in financial markets and good weather conspired to keep customers away.

The employee-owned group, seen as a barometer of Britain's retail sector, said sales also fell 0.7 percent at its upmarket Waitrose supermarkets in the week ended September 27.

"A combination of unseasonably sunny, warm weather and a huge amount of coverage of the global economic situation added together to give a very tough trading week," John Lewis said of its department stores.

Shoppers are curbing spending amid higher food and fuel costs, sliding house prices and growing economic uncertainty due to the crisis in financial markets.

On Thursday, landmark retailer Marks & Spencer reported its worst quarterly underlying sales performance for three years, and fashion label Ted Baker said recent trading had been hit by financial market turmoil.

On Friday, outdoor retailer Blacks Leisure said it expected a wider first-half loss, while newspaper distribution and airlines services firm John Menzies warned that profits at its aviation unit would miss expectations.

John Lewis said sales fell at all but one of its department stores that have been open for more than a year.

Sales of home-related products were down 13.3 percent, while electricals and home technology sales were down 7.2 percent and fashion sales down 6 percent.

Despite the weak performance, John Lewis said it was continuing to take market share.

It also said sales of fitted kitchens, large electrical items and flooring performed strongly amid signs that Britons are choosing to improve their homes rather than moving.

(Reporting by Mark Potter; Editing by Greg Mahlich)