* John Lewis weekly department stores sales up 1.2 percent
* John Lewis weekly grocery chain sales leap 40 percent
* Analysts say spending flurry likely to be short lived
* Experian says shopper numbers down 9.7 percent on Jan. 1
(adds latest Experian data)
By Mark Potter
LONDON, Jan 2 (Reuters) - British retail bellwether John Lewis reported a surge in sales in the days immediately before and after Christmas, but data on shopper numbers suggested a run of holiday bargain-hunting may already be coming to an end.
Market researchers Experian said on Friday shopper numbers on Jan. 1 were down 9.7 percent on the same day last year.
"This weekend will be critical for retailers as they focus on shifting stock," said Experian analyst Anita Mason.
Previously, Experian reported a big rise in footfall in the days before Christmas and for the start of the traditional post-Christmas clearance sales -- trends confirmed by department stores and supermarket group John Lewis.
The employee-owned group said on Friday that sales at its 27 department stores rose 1.2 percent to 71.03 million pounds ($103.5 million) in the week ended Dec. 27 compared with the same period last year, while turnover at its Waitrose supermarkets rocketed 40.6 percent to 111.29 million.
John Lewis did not publish a figure for sales in the week ended Dec. 20, but prior to that the group had reported falling sales at its department stores for 13 straight weeks.
Britain's retailers are struggling as indebted shoppers curb spending amid rising unemployment, sliding house prices and fears of a deep recession.
"The pundits who predicted it would come fast and furious in the final week were on the money," said department stores retail director Patrick Lewis on the jump in pre-Christmas spending.
The chain had previously announced that Dec. 27 -- the first day of its clearance sale -- produced record takings as shoppers flooded stores looking for bargains.
"The pace has kept up at the same healthy rate for the first two days of this week," Lewis said.
A 25-percent jump in fashion sales offset a 20.5 percent plunge in sales of home-related goods. Sales of electricals and home technology products were down 1.2 percent.
Waitrose had previously reported a big rise in pre-Christmas sales, including its busiest ever trading day on Dec. 23.
However, analysts fear the spending spree will be short lived and will not provide much respite to retailers because they have had to slash prices in order to attract custom.
"We strongly suspect that the sales effect will be temporary and that retailers will face a desperately difficult 2009," said IHS Global Insight economist Howard Archer.
"This will keep pressure on them to price competitively..., which will obviously impact on margins. As a result, many more retailers seem likely to go under in 2009."
Sweets-to-DVDs chain Woolworths and furniture group MFI both went into administration, a form of creditor protection, in the run-up to Christmas, and several smaller companies have followed suit in recent days.
Accountancy PricewaterhouseCoopers confirmed on Wednesday that it had been appointed as administrator to Adams, Britain's biggest independent childrenswear retailer, putting a question mark over around 3,200 jobs.
Marks & Spencer, the clothing, food and homewares retailer, is due to report on its Christmas trading next Wednesday. Fashion group Next and department stores chain Debenhams report on Tuesday, with supermarket group J Sainsbury on Thursday. (Editing by Hans Peters, Mike Nesbit, John Stonestreet)