A business group representing 2,500 businesses in Dublin has urged all parties in the rail dispute to find a resolution.
The group DublinTown has said that the threatened rail strike starting tomorrow will cost businesses in Dublin €30m a day.
Thousands of commuters and travellers face disruption over the imposition of train workers temporary pay cuts.
SIPTU and National Bus & Rail Union members are holding five days of industrial action tomorrow, Monday 25 August, Sunday 7 September, Monday 8 September and Sunday 21 September.
Iarnród Éireann formally advised the trade unions and employees that the company will implement measures to achieve payroll savings across its workforce from tomorrow.
The proposals for pay cuts have been accepted by members of TSSA, TEEU and Unite trade unions but were rejected by SIPTU and the NBRU.
Iarnród Éireann corporate communications manager Barry Kenny said the company had always made clear there was no other option given it was facing insolvency.
NBRU general secretary Dermot O'Leary said members are being asked to take great risks if they accept pay cuts across the workforce of Iarnród Éireann.
Mr O'Leary said workers are being asked to "put their hands in their pocket, to take shot in the dark, a pig in the poke, with no guarantee of the future of the railway."
Mr O'Leary added "it is regrettable that the impact of the company's decision to cut our members wages will be widely felt by those who use the train as a mode of transport. In making their decision the company, supported it would appear by the Minister, have chosen to ignore the concerns of staff in relation to the future of the railway"