The backlog of letters, parcels, bills and presents is already so large it could affect the Christmas post according to a senior member of the Communication Workers Union.

The CWU's London representative, Martin Walsh, says unless the union and the Royal Mail come to an agreement by the second or third week of October, the backlog will impact on Christmas.

The union is now claiming 25 million items are being held in the backlog mountain, with some items taking two weeks to deliver.

A Royal Mail spokesperson says this figure is exaggerated and every item is being delivered.

The CWU is balloting its 121,000 members on a proposed national strike – the results are expected at the end of next week.

And if the strike does go ahead, the Royal Mail is set for more disruption by the end of October or the beginning of November.