A rail strike this weekend is expected to hit thousands of travellers, including GAA fans heading to Croke Park for the All-Ireland football semi-final on Sunday.
SIPTU and National Bus & Rail Union members are holding five days of industrial action on Sunday 24 August, Monday 25 August, Sunday 7 September, Monday 8 September and Sunday 21 September over plans by the company for pay cuts.
Iarnród Éireann formally advised the trade unions and employees that the company will implement measures to achieve payroll savings across its workforce from Sunday 24 August.
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.
Speaking on RTÉ's Morning Ireland, Minister for Transport Paschal Donohoe said going ahead with the industrial action would worsen the situation at the company.
He said: "I continue to emphasise two points, first that with the time still available that this strike should not go ahead.
"90,000 people are going to be inconvenienced over these days, over a temporary wage cut of 1.7%, and the second point is that if these strikes go ahead - and it's likely that at least one will at this stage - that it makes a very difficult situation within Irish Rail (Iarnród Éireann) even more fraught."
Mr Donohoe said that between 2011 and 2013 Iarnród Éireann had received €1 billion in funding.
"It is my objective going into next year not to propose further reduction in the subvention level to Irish Rail," he said.
The National Transport Authority has confirmed that Irish Rail will lose €500,000 from the public subvention if the two-day strike goes ahead, while if the additional three days of stoppages take place in September the company will lose €1.2m overall.
The NTA added that 20 private bus operators plan to add additional capacity on strike days, with details of these available here.
Mr Donohoe said strong bodies are in place to deal with industrial action in Ireland and he would not intervene in the impasse as this would be undermining their role.
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."