An unofficial strike over rosters by 21 Dart drivers caused the cancellation of a number of trains yesterday.
Morning rush hour trains were not affected, Iarnród Éireann said, but six trains were cancelled between 9am and 1pm, leading to 20 per cent cancellation of services for the day.
The company expects the service to be back to normal today.
The drivers stopped work because of a change in rosters which involved some drivers working more weekend shifts. Most of those who stopped work are members of the NBRU but the group also includes some Siptu members.
The company and drivers were scheduled to meet under the Iarnród Éireann arbitration process this Thursday to discuss ongoing roster arrangements.
Yesterday's action was unexpected, the company said, and unnecessary in the context of ongoing talks.
"We're disappointed they felt the need to take this action today, it was completely unnecessary," company spokesman Barry Kenny said.
However, the NBRU said the company had failed to abide by rostering agreements.
"Last Tuesday union representatives met with management at the Fairview depot and management gave assurances that no changes would be introduced in rosters ahead of a meeting with a monitoring group next Thursday," general secretary of the NBRU Liam Tobin said.
However, he said management had changed rosters ahead of Thursday's meeting without consultation. "A management representative came back on Friday and announced that the company was unilaterally changing rosters this week. We have proposed that drivers be allowed to continue working normally while discussions take place."
The union welcomed the company's decision to re-enter talks on the new Dart rosters on Thursday and said its members had been instructed not to engage in any protest today.
"The NBRU regrets the inconvenience to the public and remains available for talks," Mr Tobin said.
