Sales at John Lewis rose 10% for the week to November 29, compared with the previous week but sales were down 13% against the same week the previous year.
John Lewis said its decision to introduce the 2.5% reduction in VAT three days earlier than the official start date, which is today, had helped to boost sales at the end of the week.
John Lewis said that the initial VAT cut announcement by the Chancellor last Monday had impacted sales at the beginning of last week as shoppers held off and waited for the price reductions to be implemented.
John Lewis also blamed the collapse of Woolworths and MFI last week for hitting consumer confidence at the start of the week.
John Lewis said that fashion, toys, gifts, Christmas trees, craft products and beauty sold well during the week.
John Lewis director of retail operations Patrick Lewis said: "The next three weeks' trade will be crucial to the high street. We are confident that John Lewis' strong and innovative Christmas products, services and price matching will ensure our continued position as market leader."