Negotiations to sell the 27-store group to US chain Gristede's for about £120 million were expected to be concluded by now. M&S chairman Luc Vandevelde told the City to expect an announcement by the end of January. But after a last-minute wrangle on price, the deadline was extended by a further three weeks. Both sides claim the deal is still on track, but warn investors not to expect completion before March 31.