LONDON, Jan 2 (Reuters) - John Lewis, Britain's No. 1 department store group, saw year-on-year sales slip 1.4 percent in the week to Dec. 27 as earlier promotions cooled demand in the run-up to Christmas.

The employee-owned firm said on Friday revenue for the week stood at 126.24 million pounds ($196 million) and included a strong start to its clearance sale with online orders on Christmas Day up 19 percent.

Due to calendar timing, however, some of the sales demand would not show until next week's numbers, the group said, as the Christmas week only included one full-day of its in-store clearance sale.

The performance follows a 2.4 percent fall in year-on-year sales for the previous week to Dec. 20, as record figures from November's Black Friday deals resulted in lower demand for home technology such as TVs and iPads.

On Tuesday British clothing retailer Next posted a 2.9 percent rise in sales in the run up to Christmas, towards the upper end of its predictions, without resorting to the discounting frenzy seen at many of its peers. [IID:nL6N0UE0S2]

($1 = 0.6435 pounds) (Reporting by Neil Maidment; editing by Kate Holton)