Taoiseach Leo Varadkar says the cost of running the new National Children's Hospital needs to be benchmarked against similar hospitals around the world.
Construction costs for the hospital have jumped to more than €1.4bn and could rise further.
It is due to open in 2022 at St James Hospital in Dublin.
Mr Varadkar said: "I think one thing we need to plan for now is to make sure that, as the hospital is commissioned, that we benchmark the cost of running it with similar hospitals around the world.
"It's one thing to have a very expensive hospital that costs more to build than we planned, but if it costs more to operate than we planned, that's an overrun every year