Bosses were forced to axe trains on the main Dublin to Cork line over the Bank Holiday weekend while further disruption is planned today.
Last night, Irish Rail said the drivers were in defiance of instructions from their own unions, the NBRU and SIPTU, to carry on working while talks are held to resolve grievances.
“The ongoing breach of company-union agreements by some train drivers is unsustainable and must cease immediately,” said a statement from Irish Rail.
“Iarnród Éireann calls on drivers to immediately guarantee full services as required under company-union agreements, and engage in the accelerated talks process which they themselves sought.
“(Otherwise) the company will be forced to consider all possible options to resolve the impasse.”
The company and the unions are in arbitration to hammer out a deal over grievances on working hours and efficiencies.
On March 18 the unions instructed their members to work as normal while talks progress but most drivers are ignoring the orders, said Iarnród Éireann.
Over the weekend more than a dozen services, including four trains on the Dublin Heuston to Cork route, were cancelled.
Today a number of services from Dublin Connolly are either cancelled or replaced by buses.
“The company has at all times endeavoured to avoid taking any action which could have the potential to cause more widespread disruption,” said Iarnród Éireann.
The wildcat industrial action began in December and has caused disruption at short notice to passengers.
The Rail Users Ireland group, which fights for passengers’ rights, said the reason for the industrial action was a shortage of drivers.
Spokesman Mark Gleeson said drivers were being asked to work on days off, but were insisting on sticking to their agreed rotas.
Unions said their members were unhappy over a number of issues, including a shortage of drivers as well as the pace of talks over the past two years.
* See www.irishrail.ie for the latest on travel information.