Staff working for beleaguered Consignia have accused managers of heavy handed tactics in their desperate drive to cut costs.

The Northern Echo has learnt that postal workers have been threatened with the sack for delivering unstamped mail for colleagues.

Unions say the practice has gone on for years and claim managers are among those who have taken advantage.

Now, as the postal group seeks to cut a further 17,000 jobs following a recent £1.1bn loss, internal memos have been sent to staff warning of disciplinary and possible criminal action over the practice.

One worker at the Darlington sorting office in County Durham has already been fired, but reinstated on appeal.

A member of staff, who did not want to be named for fear of further action, said: "Because of the need for redundancies in the business they are using any means necessary to get rid of staff."

Phil Graham, branch secretary of the Darlington branch of the Communication Workers Union, said: "Delivering unstamped mail is an offence and you can be disciplined for it.

"But I have been a postman for 28 years and this has been overlooked for a long time.

"I have known managers who have asked me to deliver unstamped mail when I've been out on deliveries.

"You're probably talking about one of our members asking a colleague to deliver the odd birthday card or something like that."

Under-fire Consignia has already shed 13,000 jobs in a bid to reverse record losses.

Chairman Allan Leighton has also announced it is to get rid of its much ridiculed name at a cost of £1m.

The postal group, which is losing about £1.2m every day, will rebrand itself with its old name Royal Mail from the end of the year.

A spokesman for the group said it would not comment on disciplinary measures taken against any individual.

She said: "Our policy states that the practice of delivering unstamped mail for colleagues or asking a colleague to deliver unstamped mail on their behalf is not allowed."