The Master of Holles Street says he believes there is clarity over ownership and governance at the new National Maternity Hospital.
It comes as two members of the Health Service Executive (HSE) board raised concern about the proposed new hospital at the St Vincent's site in Dublin.
While Health Minister Stephen Donnelly is due before the Oireachtas Health Committee later to answer questions about the development - specifically about the leasing of the land on which the hospital is to be built.
Master of the National Maternity Hospital, Professor Shane Higgins, told Newstalk Breakfast there has been separation between church and State.
"I also wish to wish to acknowledge as the Master of the National Maternity Hospital the really genuine concerns that are out amongst members of the public and members of the Oireachtas.
"I welcome this opportunity for us to be able to debate this issue in advance of the next Cabinet meeting.
"I do think there is church and State separation, and I think actually what we've seen in the last couple of weeks could be seen as yet another example of that further separation.
"The Religious Sisters of Charity, willingly and unconditionally, transferred the shareholding in St Vincent's Healthcare Group to St Vincent's Holdings and have divested themselves of their interest in healthcare in this country.
"That is an enormous separation".
'Legally robust structure'
Prof Higgins says the 299-year lease on the land which the hospital is being built on has worked in other instances.
"Long lease hold ownership is a tried and tested legal ownership structure for centuries.
"More recently it's been in areas such as shopping centres, industrial parks, university campuses - and indeed hospitals.
"I think we have to also consider the actual building.... the building will have elements of St Vincent's Healthcare in it, it will have the National Maternity Hospital and it will have shared services.
"And where the new hospital facility will physically adjoin existing buildings on the Elm Park campus - and contain an area that is used exclusively by St Vincent's Healthcare Group - it will house also critical shared infrastructural properties.
"The transfer of the freehold in the land and buildings to any party would be neither legally appropriate nor practically workable.
"So the proposed legal structure is an established and sufficiently legally robust structure to protect the interest of both the State and the new National Maternity Hospital".
And he says the current status of the hospital will not change.
"We're not a State-owned, State-run hospital - we are a voluntary hospital.
"[It's] a condition that we hold very dear to us because we feel it's very important to allow us to provide the services that we do provide to patients.
"And that's exactly what we're going to be under the new DAC constitution in Elm Park".