London Midland has rejected the latest recommendations from the Department for Transport to improve the Abbey Flyer.

Politicians from St Albans and Watford have written to the government department regarding their concerns about the service, which joins St Albans Abbey Station and Watford Junction, which is regularly cancelled and delayed.

St Albans’ MP Anne Main and Watford MP Richard Harrington initially made contact to follow up a proposal made three years ago to move from a heavy rail system to light rail.

However transport minister Norman Baker has written to the pair to say that this would not be possible due to the high cost to the taxpayer.

Despite this, Mr Baker’s letter showed his concern about the current state of London Midland’s service.

He said: "The franchising is still several years away and I would like to see improvements to the line which will benefit people who use it more quickly.

"When funding and the business case permits, I would like to see the infrastructure along the line improved to enable a more frequent service to be introduced, such as by adding a new passing loop."

However London Midland told the department that it is unable to allocate superior rolling stock on the line.

Daniel Scaife, a spokesperson from the train operator, said: "We have worked hard to investigate a range of options to increase service frequency.

"Our extensive testing of running trains faster on the single line demonstrated that, ultimately, infrastructure constraints prevent the introduction of a half-hourly service on the Abbey Line.

"Achieving an increased frequency requires a significant upgrade in infrastructure including the installation of a passing loop which would allow trains to pass each other on the single line."

Mr Harrington has hit out at the lack of improvements, saying that it is "not acceptable".

He said: "It is called the Abbey Flyer but it is more like the abbey crawler.

"I’ve got a large group of constituents who are really upset about the poor service. People are annoyed about it.

"It is disgraceful. This is not acceptable.

"[The Department for Transport] must keep this in mind when the renewal comes up.

"We’ve got to get them to concentrate on this."

Mrs Main added: "I have met with the ABFLY group in St Albans to discuss this issue and I am very disappointed that there is no prospect of upgrades to the line.

"I believe that this is short sighted of London Midland and we are missing a good opportunity to improve services and increase local passenger usage of public transport."