Royal Mail will regain its monopoly on delivering household post following a decision by Express Dairies to pull out of the postal delivery business.

Express Dairies, the milk business owned by Arla Foods, the Danish group, has been delivering small parcels, magazines and catalogues to the nation's homes using its fleet of milk floats since 2002. Although other companies have contemplated setting up a full residential mail delivery service, so far Express has been the only competitor to Royal Mail in this market.