Taoiseach Enda Kenny has said that politicians in the North must remember they were voted into positions of responsibility.
Mr Kenny is spending the day with his party to plot General Election strategies.
Arlene Foster was named acting First Minister after the mass resignation of her party colleagues amid a crisis sparked by a murder linked to alleged members of the IRA.
“The people of Northern Ireland do not want to have their future blocked by the politics of the past,” Mr Kenny told RTÉ Radio’s Morning Ireland programme.
“If the institutions were to collapse, obviously it would be a very long time before you’d get back to a situation of what you might call where you would have normal running of the Assembly.
“I think this can be avoided but I think it needs a realistic appraisal by people who have had very harsh things to say about each other and where there are clear differences of opinion, strong differences of opinion, but you have to look at the bigger picture, and that’s the people of Northern Ireland and their futures.”
On the issue of whether the IRA still exists, Mr Kenny said the evidence is it does not exist as it once did in the Republic.
“But you can’t have a situation of fear along the border where people are afraid to open their mouths about anything,” he said.
“I would think the cell formation of the so-called IRA is no longer functioning in that manner but that does not mean people who were members of cells do not meet in terms of criminal activity, particularly in Northern Ireland.”