The Government is under fire for rowing back on a Comptroller and Auditor General investigation into overspending at the National Children's Hospital.
The project is now expected to cost €1.4 billion - more than twice the original estimate.
Sinn Fein is describing it as a worrying development for the planned site at St. James's Hospital in Dublin.
It says such an investigation must have been debated at the highest levels in Government.
The party's health spokesperson, Louise O'Reilly, says we need to find out why the plans for an inquiry have been shelved.
"We need to know why it's been scrapped. Is it going to be replaced with another investigation?" she asked.
"We are not talking about small amounts of money here, we're talking about spending that is absolutely out-of-control.
"The spending has trebled since the initial announcement and it doesn't look to be coming under control any time soon.
I think the Dáil needs to hear some answers.