Marks & Spencer is expected to be in a cautious mood over its first quarter results, due out on Tuesday.
Flat like-for-like clothing sales are forecast, with a modest increase of about 1% across general merchandise. Shares fell 12.5p to 631p.
Debenhams is believed to have had merger talks with European department store chains, including German firm KarstadtQuelle. The UK retailer's share price has dropped by about a third since its float in May last year, but held firm this week at 132.25p.
Sports Direct boss Mike Ashley is locked in a bidding war with investment firm Hidary Group for US boxing brand Everlast. As Drapers went to press, Ashley was in pole position after Everlast's board recommended his offer of US$33 (£16) per share. However, Sports Direct's share price dropped 15.25p to 177.75p.