Micheál Martin has said Mary Lou McDonald’s description of a United Ireland being within “touching distance” has little substance behind it.
The Sinn Féin President said earlier this week a vote on unification will happen in the next six years.
The Tánaiste said Fianna Fáil support reunification - but the focus should be on ensuring politics at Stormont works for the time being.
“These are all phrases that don’t have a lot of substance behind them,” he said.
“What does that mean ‘within touching distance?’
“My approach has been very clear, we’re a party that supports the unity of the Irish people but I think everybody needs to focus on making sure that the Executive works and the Assembly works and the politics works
“There’s been a lot of scepticism among the people of Northern Ireland in terms of politics working.”
Mandate for a border poll?
In response to calls for a unity referendum, the British Government said it saw "no realistic prospect of a border poll".
Under the terms of the Good Friday Agreement, the Secretary of State for Northern Ireland is mandated to call one “if any time it appears likely that a majority might vote for a united Ireland”.
Main image:Micheál Martin. Image: Newstalk