Strike action is now in its 18th day
Talks are continuing at the Workplace Relations Commission (WRC), aimed at resolving the dispute at Bus Éireann.
A proposal is expected to be put forward Monday evening, meaning buses could be back on the road tomorrow as workers consider it.
The deal is likely to involve at least 120 jobs going at Bus Éireann.
Willie Noone from SIPTU says they Are trying to get the best deal possible, but something needs to happen soon.
"We all know a proposal has to come out today, we've ran out of time.
"There's some hard decisions to be made here this evening - if we don't get those decisions in our favour, it's gong to change the whole concept of how public transport is provided in this country. Everyone knows that now.
"Our members are expecting a proposal that'll come out that'll protect their conditions of employment and we believe that any proposal that comes out of here has to reflect that."
The dispute centres around a proposed survival plan at the company, which involves significant cuts to workers pay and conditions.
Strike action at the bus network is now in its 18th day, with thousands of commuters and business affected across the country.
Dermot O' Leary of the NBRU said earlier both sides committed Sunday night to try and reach a resolution in 24 hours.
"Both parties yesterday evening committed to the WRC that we would endeavour to reach a conclusion to these talks in a 24-hour period.
"That's our commitment on the trade union side, and the company have - as I understand - reciprocated to that commitment.
"So that's what we need to do - we need to do it for a number of reasons.
"We need to do it because people on the picket lines now touching on 18 days, commuters have been without a service in rural Ireland and again, people need to understand that that's having a major affect on towns and cities".