Royal Mail will deliver parcels on Sunday and in the evenings in the last few days before Christmas in an initiative welcomed by online retailers.

While the growth in online retail has slowed this year, Capgemini and IMRG, the industry body, predict shoppers will spend a record £13.2bn on orders for Christmas. Royal Mail said it expected to deliver 140m items from internet orders and was stepping up deliveries on December 21 to cope with the volume.