M&S kicked off its one-day Sale this morning by blotting out the windows of its Marble Arch store with posters providing details of the 20 per cent-off promotion.

The store opened at 8am - an hour earlier than normal. The promotion, which is seen as a sign of difficult trading at the retailer, covers womenswear, menswear, lingerie, childrenswear, furniture homewares, beauty, wine, champagne and the “3 for 2 Christmas shop”.

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