ROYAL mail has been accused of allowing fraudulent letters to be sent en masse to vulnerable recipients.

Fraudsters are sending letters using Royal Mail branding to elderly Britons under its bulk mail contracts, according to an undercover investigation by The Daily Mail.

The newspaper claimed that the postal service are failing to crack down on the scam, despite being warned repeatedly for more than a decade.

The elderly victims, targeted by a self-proclaimed "mafia" who swap "suckers lists" of people, are said to lose billions each year in postal scams.

It is thought scammers pay a company to print their letters in bulk, which are taken to the UK, and firms provide the Royal Mail with the letters which go into its system.

The letters are then delivered with the Royal Mail logo - which campaigners have warned gives them the seal of authenticity.

A Royal Mail spokesman said the service understood "the upset and disquiet this kind of mail can cause", but that it was illegal for it to open letters, and doing so would raise serious privacy concerns.

He said: "Just as newspapers would never intentionally publish advertisements that promote defective goods or illegal activities, Royal Mail never knowingly handles scam mail.

"We simply do not want to handle scam mail or make any money from this terrible activity.

That is why we cease to do business with these people as soon as law enforcement agencies alert us to scamming activity."

The service said it has passed on the list of suspected companies supplied by The Daily Mail to its partners at the National Trading Standards' scams team for investigation.

Baroness Ros Altmann, former minister of state for pensions, said it was shocking that Royal Mail's "trusted brand" was being used to give credence to the scam letters.