A rail company has been branded “pathetic” by Watford MP Richard Harrington, as an ongoing dispute with staff continues to inconvenience travellers.

London Midland services, which run between Watford Junction and London Euston, have suffered repeated delays in recent weeks, as an overtime dispute between drivers and management rumbles on.

The company is being forced to cancel many off peak services because drivers belonging to the ASLEF union are refusing to work overtime in a row about pay for Sunday shifts.

Mr Harrington, who has called an urgent meeting with company bosses, said staffing problems were not a valid excuse for any business – especially one providing a public service – to deliver substandard results.

He said: “This has been a problem for a long time and clearly it has got out of hand. It is disrupting people’s lives and has been going on for too long.

“The system is dependent on drivers working overtime but they don’t want to work it. That is really not good enough.

“I’ve worked in private business for 35 years, and in private business staffing problems could never be used as an excuse. They have got to provide a service and I find that excuse pathetic.

“Engineering works I can understand but I am really not happy about this. I have booked a meeting at the highest possible level and if I do not get a satisfactory response I will be taking it to the regulator. If I still do not get a satisfactory response I will go to the government.”

London Midland, which says it is not alone in relying on overtime volunteers to operate a consistent service, is now publishing lists of affected services 24 hours in advance and a seven day “traffic light” forecast predicting potential disruption.

Although the main bulk of the disruption has been felt on Birmingham lines, London Euston services are rated as red on Friday and amber for all other weekdays.

The company, which is also keeping passengers updated on the social networking site Twitter, says it has set up a dedicated team to ensure maximum services on each day but says simply employing more drivers would “not necessarily” combat the problems.