Royal Mail has been accused of a failure to crack down on scammers use the postal service to contact vulnerable people.

The Daily Mail says that letters sent via bulk mail contracts appear to be trustworthy as they feature Royal Mail branding on the envelopes, with people said to have lost money after responding to the fake offers.

Royal Mail says it is illegal for them to open letters, preventing it from stopping fraudulent post deliveries.

The firm said it understood the “upset and disquiet” that scam mail causes the public.

The company stated: “We have closely examined the list of companies suspected by the Daily Mail of sending scam mail. We have already passed it to our partners in the National Trading Standards Scams Team so that they can investigate further.”

It is alleged the scammers pay a firm to print their letters in bulk which contain messages from fake clairvoyants, prize-draw scams and illegal advertisements for unlicensed health remedies.

If printed abroad, the letters are then taken to the UK and firms here sort and mass transport them to Royal Mail, which makes the final delivery to peoples’ homes.

The Royal Mail logo is printed on the envelopes.

Whistl is one of the firms which provides Royal Mail with the letters to deliver.

In a statement on its website it said: “Scam mail is a terrible abuse of the postal system and it is unacceptable how vulnerable people are targeted by these scammers. Scamming is also not isolated to mail but is frequently carried out using other methods of communications such as email, text and through social media channels.”

The firm said once made aware of scam mail it acts to “terminate the relevant contract” with the organisation involved.

“But we acknowledge as an industry we need to do more,” the company added.