The Royal Mail has rejected claims by the Communication Workers Union that recent postal strikes have created a backlog of over 20 million items.
The CWU has said that it's ongoing series of localised strikes have caused a backlog of nearly 22 million items, of which 20 million are in London.
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However a Royal Mail spokesman dismissed the figure saying, "The amount of mail delayed in the capital is absolutely not the 20 million figure claimed by the union but nearer to four to five million letters, which we expect to clear in the next few days."
The company also said that well over 90 per cent of it's first and second class items had been delivered in good time and that more than 90 per cent of its staff were working.
The dispute centres around the proposed modernistion of Royal Mail, which has suffered from a yearly drop of 10 per cent in mail volumes.
Royal Mail claims that all changes to working practices and modernisation plans were agreed in a deal with the union following the 2007 national strike.
The CWU disputes such claims and says that the company is now trying to force through changes which have not been agreed. The CWU, which till now has organised only localised strikes has now called for a ballot of 130,000 workers for a national strike.
The result of the ballot will be announced on 1 October and will coincide with the last day of the Labour party conference - a potential embarrassment to the ruling party, which is already languishing in the polls.