The regulator said Royal Mail's universal service obligation, which means it has to charge a uniform rate for delivery to all parts of the UK, should be scrapped for Mailsort 120, Mailsort 700, Walksort, Packetpost, Flatsort and Presstream.
Nigel Stapleton, Postcomm chairman, said the regulator believed the decision went a long way to reflect Royal Mail's wish to have the freedom to compete in a liberalised postal market.
However, a Royal Mail spokesman said Postcomm had "left the handcuffs on" the company, and it should be allowed to compete with other operators in all bulk mail services and before April.
"The products left as universal services account for about a quarter of the bulk mail market," he added.
Postwatch also criticised the move but from the opposite standpoint, saying the changes were being introduced too early.
"Competition is just starting to develop and the market is seeing an awful lot of change. We would rather that the regulator allowed pricing in proportion to come in first," a spokesman said.
Postcomm decided in June last year that the universal service obligation should remain on stamped mail and products applying to single items of mail.
It has now decided that obligation should still apply to Cleanmail, which does not require users to have sorting machines and is the service used by most small businesses, and Mailsort 1400, which covers mail up to 2kg in weight and is pre-sorted according to the locations of the 1,400 delivery offices.
Separately, Postcomm is currently consulting on the issue of long-term licences to Target Express, for collection and sorting, and for Intercity Communications, for bulk mail services, collection and sorting, and tracked business-to-business services.
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