The Government was "asleep at the wheel" regarding the National Children's Hospital cost overrun, the opposition leader has said.
Micheal Martin said a 450 million euro under-estimate should have been queried earlier by ministers.
Consultants PwC have identified "significant failings" in planning and budgeting in a report into the matter.
Mr Martin told the Tanaiste: "They were asleep at the wheel.
"They made the glitzy announcements but challenged very little indeed."
He added: "The announcements were made but no one asked any hard questions at ministerial level."
He said management was "shambolic".
Simon Coveney said there was a "gross under-estimate" of what it would cost to build the hospital.
He added: "There should have been red flags earlier in the system.
"There was not and we need to learn lessons from that."
Sinn Fein leader Mary Lou McDonald said the health system was in perpetual crisis.
She branded the flawed process a scandal.
She said: "Members of the Government need to be reminded that they are not spectators to all of this.
"They are the authors of this fiasco and they are the people that are responsible.
"Who is accountable for the clear and gross incompetence?
"Administrative incompetence, professional incompetence and political incompetence.
"Who is accountable for that and who will be held accountable?"
The cost of the hospital is 450 million euro higher than the 983 million euro approved by the Government two years ago.
