Postmen at the heart of the Wimbledon mail crisis have hit out at Royal Mail claims that a three-week backlog of letters has been caused by strike action.

Reports of mail strewn across the pavement outside Wimbledon’s sorting office made national headlines at the weekend as a mountain of undelivered letters continues to grow.

But postman have said incompetent management and last month’s decision to reduce working hours and delivery rounds has plunged the system across SW19 into chaos, long before a series of one-day strikes taken by the Communication Workers Unions started.

A controversial new computer system used to calculate delivery routes has led to 61 planned job losses in Wimbledon - a third of its workforce - and the removal of 23 delivery rounds.

Postman have also claimed that more than 20 managers and dozens of agency staff drafted in to clear the backlog are making the situation worse due to a lack of experience.

One postman who did not wish to be named, said: “A colleague of mine even had to explain to a manager attempting to sort mail what was meant by odd and even numbers. She explained that she had not been speaking English for very long.

“I delivered post with three of the seconded managers on various routes and days when, despite there being two of us, we only managed to deliver at most three quarters of one of the new rounds.

“These managers unanimously agreed that the workload was mad and many commented that they had never seen such a shambles or such poor management as in Wimbledon.”

Wimbledon MP Stephen Hammond has demanded talks with Royal Mail management, nationally and in Wimbledon.

He said: “The situation is simply unacceptable. Incompetent management is letting the people of Wimbledon down.”

But a Royal Mail spokesman said: “The reason for any mail delays in Wimbledon, which Royal Mail very much regrets, is because of strike action by the CWU and it is nonsense to suggest otherwise.”