A rail company was branded “pathetic” by Watford MP Richard Harrington as an industrial dispute with staff continued 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 rumbled on.

The company had been forced to cancel many off-peak services because drivers belonging to the Aslef union were refusing to work overtime shifts in a row about pay and conditions – causing weeks of disruption to passengers.

A deal between the two parties was provisionally agreed on Wednesday, but Mr Harrington is still demanding a meeting with company bosses to ensure that similar problems do not happen again.

He said: “I am pleased that an agreement has been reached but it has dragged on for far too long. It is not an option for them to provide this service – it is a statutory obligation and I am not happy about what has happened.”

Drivers had refused to work overtime shifts during the dispute, causing chronic staff shortages and cancelled services – especially at weekends, when overtime demand is at its highest.

Mr Harrington, however, claimed that was not a valid excuse for the recent disruption. Speaking on Wednesday he said: “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.”

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

Severe disruption is predicted today (Friday) but it is hoped services will return to normal over the weekend.

A threat of strike action has also been lifted.

The causes of the current dispute can be traced back to 2007, when London Midland was formed from the disbanded Central and Silverlink franchises and negotiations into harmonised pay and conditions commenced.

The Aslef union, which represents 605 of the company’s 614 drivers, reached a preliminary agreement yesterday and has advised its members to accept the deal.

London Midland's operations director, Wallace Weatherill said: "This is good news for our passengers and staff and we will now renew our focus on delivering a reliable train service.

“We know passengers in Watford and across our network have suffered disruption and we would like to apologise to them and thank them for their patience.”