Mr Neligan has said he suspects there was a major political input in the decision, something he felt had no place in the discussion.
“There is a lack of transparency about all this and certainly there is lack of transparency about how the original selection was done.”
Mr Neligan agreed that the political pressure behind the plan for the €600 million development being located on the Mater Hospital site in central Dublin was due to its location within the constituency of former taoiseach Bertie Ahern.
The decision to locate the hospital, which will amalgamate Dublin’s three existing children’s hospitals — the National Children’s Hospital, Tallaght; Our Lady’s Children’s Hospital, Crumlin and Children’s University Hospital, Temple Street — on the Mater site was made despite criticisms concerning lack of space and access from outside Dublin.
Greenfield sites with easy access to the M50 were overlooked in the decision to locate the hospital on the Mater site.
However those who support the plan point to the benefits of the hospital being located alongside a major adult facility.
Mr Nelligan told RTÉ news he had reconsidered his initial backing for the plan in light of a visit to the proposed site.
“There is no green space, nothing to look at. It doesn’t seem now to me to be the best thing for the children.”
According to Mr Neligan many of the international experts whose backing was given to the proposed plan were not actually consulted on the site but other aspects of the project.
He added: “It is time to draw back before you dig the hole in the ground and go up 16 stories. It is not about just the children from Dublin, there is tertiary referrals, they have to come from Cork, they have to come from Limerick, from Sligo from all over the country.”
Construction work has not yet begun, but some €23m has already been spent on contracts, ranging from business services and project design to public relations. In its revised national development plan published earlier this week the Government also renewed its commitment to investing €400m in the project.
A Department of Health spokesman said plans would continue.
“The department is aware of Mr Nelligan’s comments. The project is advancing to schedule under the direction of the National Paediatric Hospital Board. A detailed design brief has been finalised and the board is preparing to submit for planning permission, ” he said.
The plan also received the continued backing of outgoing HSE chief executive Brendan Drumm.