Talks between Siptu and Bus Eireann over school bus drivers' pay and working conditions are set to begin at the Labour Relations Commission on Wednesday, in an attempt to avert strike action.
However, the workers union has said strike notice issued by hundreds of school bus drivers today over the row will remain in place.
"The issues have been outstanding for many years and the drivers remain the lowest paid employees in either the education or transport sectors," Siptu said in a statement.
Earlier today Siptu told Bus Éireann management the drivers would begin industrial action with a one-day work stoppage next Friday, November 30th, in a bid to gain parity for school bus drivers with their full-time colleagues.
Bus Éireann had called on the union to defer strike action and instead attend talks with the company at the Labour Relations Commission (LRC).
Bus Éireann spokesperson Erica Rosengrave told ireland.com: "We have agreed to talk about the issues, so we are calling on Siptu to come to talks at the LRC and to defer the strike".
Siptu says over 200 school bus drivers currently earn €11.66 per hour and have no pension entitlements, sick pay or other benefits. Siptu national industrial secretary, Michael Halpenny said the current pay rate for school bus drivers did not reflect the professionalism and demands of the job.
He said wages were so low, that even if such part-time drivers were allowed work a 39 hour week, many of them would require family income supplement to support their families.
Bus Éireann, however, says the issue has already been raised at the LRC and was rejected by the Labour Court, but insists the company is willing to discuss the matter again.
Siptu says it has been campaigning on behalf of school bus drivers for the past five years and strike action is a "last resort".
"This is very much a measure of last resort and we would make one last appeal to the company, and the Minister for Education, to do this dedicated group of workers justice," said Mr Halpenny.
The demands of the job have increased significantly over time, especially where safety and disciplinary issues are concerned, he added.
Citing the death of school bus driver Eugene McGreevy - who died saving the lives of 26 students on board his bus last month when it was involved in a collision in Co Roscommon - Mr Halpenny said: "These drivers are committed professionals, but Bus Éireann and the Department of Education are using their part-time status to deny them the sort of pay and standard benefits that their full-time colleagues enjoy".