UPDATE 1-John Lewis may rein in Black Friday push next Christmas

* Like for like sales rose 4.8 pct in five weeks to Dec. 27

* Black Friday delivers biggest sales week in firm's history

* MD says Black Friday may have reached "high water mark" inUK (Adds detail, MD comments)

By Kate Holton and James Davey

LONDON, Jan 5 (Reuters) - British department store chainJohn Lewis enjoyed the most lucrative week in its150-year-history thanks to "Black Friday" business which helpedto drive sales nearly five percent higher in the five weeks toDec. 27.

However, the company said the late November discountingbrought by the import of Black Friday from the United States wasdisrupting traditional Christmas trading patterns and may haveto be tempered.

Managing Director Andy Street questioned whether it washealthy for the retail industry to concentrate so much businesson one day, followed by a relatively flat period afterwards.

"The answer is probably not," he told BBC Radio on Monday.

"So my expectation is that Black Friday might even havereached a high water mark in the UK and we'll actually be farmore considerate next year about whether we want as an industryto concentrate business all in that day," he said.

While sales in the Nov. 28 Black Friday event were led byelectricals and home technology, the most popular gifts forChristmas included fitness trackers, coffee machines and kitchenappliances, the employee-owned group said.

Sales in the five-week period hit 777 million pounds ($1.2billion), up 4.8 percent on a like-for-like basis on a yearbefore, driven by a 19 percent jump in online sales. Shop saleswere level with last year.

John Lewis, Britain's biggest department store group, outperformed many of its rivals during the economic downturn,due to its strong online offering, modern stores and moreaffluent customer base.

The jump in online demand meant some 36 percent of all groupsales were conducted via the johnlewis.com website during theChristmas period, with more than half of those being collectedin shops via the "Click & Collect" delivery option.

The group is one of the first in the British sector toreport on its performance in the weeks running up to Christmas,a key trading period.

Retailer Next said last week it had enjoyed a solidrise in Christmas sales, especially online, without having toresort to the discounting seen on many shopping streets.

Updates are due this week from Marks & Spencer andsupermarket groups Tesco and Sainsbury.

For the year ahead, many retailers are more optimistic ontheir prospects given rising incomes and higher employment inBritain. ($1 = 0.6491 pounds) (Editing by David Holmes/Keith Weir)