Brendan Howlin admits any sort of snap election would not be good for his party.
Two weeks ago, the Labour leader announced at his party's annual conference that a party rebuild was underway to draw back people who had drifted away.
It is now just two days until Enda Kenny is expected to outline his plans for stepping down as leader of Fine Gael.
Deputy Howlin said: "An election in the medium term is inevitable. Whether it comes in the immediate aftermath of a change of leadership in Fine Gael will be a matter for Fianna Fáil.
"In an ideal circumstance, I would like five years to rebuild (the Labour party) - I would like to have local elections first - but we're not going to get that. So, we have to adjust to the reality and make the best of the situation we have."
Meanwhile, The Labour leader said he think a united Ireland can happen, if handled the right way.
"I genuinely think that's possible," he said, "(if the process) gives manifest expression to people's British-ness as well as to people's Irish-ness, and to our shared history and tradition."