The Tánaiste and Labour party leader Joan Burton has said she does not believe a coalition election pact would secure more seats for Fine Gael.
The pact has been agreed by senior figures in Fine Gael and Labour, but has received a mixed response from the parties' backbenchers.
It is to be discussed at the Labour party think-in next week, but will not be put to a vote.
Pro-pact Labour TD and Junior Minister Kevin Humphreys said: "We've operated very well with Fine Gael over the last four and a half years in government, so it would be natural in many ways for Labour party voters to vote for our colleagues in government and vice versa."
His is not a viewed shared across the party however, with Meath TD Dominic Hannigan against it, for example. The Tánaiste said Hannigan and others would be listened to - but there would not be a vote on the pact.
Meanwhile, Fine Gael backbencher Alan Farrell has said he believes the two parties should go further than a voting pact and suggested joint policies between the parties in areas including health, justice and social welfare.
He said: "There is an opportunity for us to (jointly) present certain aspects of the manifestos of both parties in areas where we can most likely agree...perhaps in the areas of justice, law and order, social welfare and health."
Joan Burton denied the pact could result in more Fine Gael TDs getting elected by getting over the line after Labour candidates with lower support levels are knocked out.