
The news comes as the row between Royal Mail and the postal workers' union escalates. A fresh wave of postal strikes starts this week, with more than 15,000 workers walking out in the dispute over jobs, pay and services.
Plans to part privatise Royal Mail, championed by business secretary Lord Mandelson, were put on hold earlier this year after objections by more than 140 Labour MPs. The business secretary argues that outside investment, to help pay for modernization of the postal service, is the only way to save Royal Mail.
In response to Royal Mail's plans to increase automation of its service and cut jobs, the CWU has been staging strikes across the country.
The unrest could get worse, with more than 100,000 postal workers are being balloted on a national strike, with the result due on 9 October.
about the effect of the strikes on their businesses.