The Taoiseach Leo Varadkar has said he has total confidence in the Health Minister, Simon Harris.
It comes as documents show Minister Harris was aware of a possible €400m overrun at the national children's hospital in August last year, seven weeks before he told the Taoiseach or the Finance Minister Paschal Donohoe.
Mr Varadkar has said concerns about the impact that had on budget planning are a red herring - as capital expenditure was decided last February.
He said even if Mr Harris had told him about the overruns earlier, he would have instructed him to do exactly what he did.
Speaking in Belfast this afternoon, the Taoiseach reiterated that he has 'absolute confidence' in Minister Harris.
He added: "Obviously I'm not going to preempt what he says in the Dáil next week - I'm sure he'll want to write that statement for himself."
He insisted Minister Harris handled the situation correctly.
“If Simon Harris had told the Government earlier about the emerging overrun, I would have told him to do exactly what he did,” he said.
“Which is to get to the bottom of it; to minimise the overrun; to find out what the reasons were and to come back to Government with options – and that is exactly what he did.
“And it would not have impacted on the Budget Day package in any way.”
Leo Varadkar says he has absolute confidence in Simon Harris as health minister. Says it wouldn’t have impacted budget talks if he had been informed earlier pic.twitter.com/iYoqaOql50
— Seán Defoe (@SeanDefoe) February 8, 2019
Fianna Fáil TD Sean Fleming has said he thinks Minister Harris has to resign.
"If he doesn't step down, this issue is going to continue... and it will undermine the entire Government.
"And if the Government wants to restore the confidence and supply agreement to a proper level of trust, the Government should do the right thing".
"He should resign today."
Taoiseach Leo Varadkar has said he has total confidence in Simon Harris | File photo | Image: Eamonn Farrell/RollingNews.ie
Meanwhile, Sinn Féin leader Mary Lou McDonald has written to Fianna Fáil leader Micheál Martin, asking him to "make clear" whether he has confidence in Health Minister Simon Harris.
She has also asked if he support a confidence motion in this regard.
She said: "This morning I wrote to the Fianna Fáil leader Micheál Martin and challenged him to stop protecting Minister Harris by way of his confidence and supply arrangement.
Mary Lou McDonald has written to Micheál Martin
"I urged Deputy Martin to refrain from using Brexit as an excuse to tolerate and enable bad government.
"Fianna Fáil must now make clear whether they have confidence in Minister Harris and if they will move or support a confidence motion in this regard."
Labour's Alan Kelly told Newstalk Breakfast he believes there are more details yet to emerge.
"I don't believe we're at the end of this, I think there's further information that's probably going to have to come out.
"I think we're going to need to see all the correspondence between the Department of Health and the Department of Public Expenditure.
"I know there was a request from the Department of Health to the Department of Public Expenditure for meetings - those meetings did not take place.
"There needs to be serious questions asked as to why that didn't happen given the volume of the overspend - and given the fact that the Department of Public Expenditure actually were over the financing of this".