David Reed, MP for Exmouth and Exeter East, recently led a parliamentary debate on the issue, highlighting the impact of delays and declining service standards across his constituency.
He said: “If there was one word to sum it all up, it would be trust.
“Trust in the Royal Mail service and in an institution that has been a constant in British life for over 500 years.
“But we all know that that trust is waning.
“Prices have increased, but the service has gone down.
“That is completely unacceptable.”
Mr Reed pointed out that Royal Mail has failed to meet its statutory delivery targets for three consecutive years.
The company is required to deliver 93 per cent of first-class letters the next working day and 98.5 per cent of second-class letters within three days, but continues to fall short.
Mr Reed raised concerns about a lack of transparency over delays and their effect on the public.
He said that in Exeter, only 71 per cent of first-class post arrives the next working day.
He added that some people are waiting up to 11 days for mail.
This includes critical items such as hospital appointment letters and DVLA letters.
Mr Reed also criticised Royal Mail for placing too much pressure on postal workers.
He pointed to larger delivery rounds and a greater focus on parcels rather than letters.
He said: “Royal Mail is not just a company; it is a British national institution.
“Be proactive.
“Communicate clearly what you are doing to improve the service.
“Most importantly, begin an honest national conversation with the British public about what they can expect.
“Only then can trust begin to be rebuilt.”