Up to one third of postal workers are likely to lose their jobs in the biggest swathe of cuts in the history of the Royal Mail, unions have been warned.

The cuts will follow increased automation and an overhaul of the way the business operates as it struggles to combat growing competition.

Royal Mail has said that the changes over the next four to five years will need efficiencies — or job losses — of 30 per cent of its full-time workforce in the letters division. With 160,000 people employed in Royal Mail letters, that means 48,000 job losses, well in excess of the 30,000 in the last round of redundancies that began five years ago.

Royal Mail has outlined its bleak vision of the future for jobs as it also tries to push through £300 million in cost cuts by the end of this year. The immediate cuts, which could also trigger job losses, have been caused because the postal group is expected to fall short of revenues for the business plan it agreed with the Government by that amount. It had to agree to stick to the plan to win a £3.9 billion bailout by the Government.

Royal Mail has also told unions that four mail centres are likely to close because of the loss of business to competitors in the mail market. Unions fear that the number of closures will be greater.

Ian Griffiths, managing director of Royal Mail letters, quit after saying that the short-term cuts were unachievable. He walked out after only a year in the job and two years after his predecessor quit within 18 months of taking the position.

Royal Mail and the Communication Workers Union, the main postal union, are in talks over pay and the restructuring of the business. Royal Mail is also discussing the closure of the final salary pension scheme to new members with Amicus.

Paul Reuter, Amicus national officer, said: “There will be potential job losses because Royal Mail is not winning business. It is only by winning new business that Royal Mail will be saved, not by cutting back on staff.”

Royal Mail said: “In an increasingly competitive market we are of course testing new, more efficient ways of working including greater automation. Until we have done this we cannot confirm the impact on jobs.”

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