The Taoiseach has described as "truly appalling" the confirmation that significant quantities of human remains were found at the site of a former mother-and-baby home in Tuam in Co Galway.
Speaking in Castlebar, Enda Kenny said the babies of single mothers involved had been treated like "some kind of sub-species".
He pointed out that this was not something that happened centuries ago in the dawn of history, but something that happened "in our own time".
Tánaiste and Minister for Justice Frances Fitzgerald said the discovery is an infinitely sad reminder of an Ireland that was a "very harsh, harsh place" for women and their babies.
She said it shows the tortured relationship the State and church had with pregnant women, saying "it is a tragedy that we are now facing in its entirety".
Fitzgerald says the Tuam discovery is an infinitely sad reminder of an Ireland that was a very harsh, harsh place for women and their babies pic.twitter.com/VS30aqQi4z— RTÉ News (@rtenews) March 6, 2017
The Taoiseach said that following the latest update from the Mother and Baby Home Commission of Investigation, the inquiry needed to proceed as quickly, effectively and sensitively as possible.
Mr Kenny said the local coroner and everyone else involved had to now see how best to progress the investigation relating to Tuam and possibly other locations.
He said Minister for Children Katherine Zappone was liaising with the commission in this regard and if its terms of reference needed to be extended then this would happen.
The Taoiseach said the discovery of remains amounted to a horrendous situation for those whose siblings had died in the former mother-and-baby home, and added that questions remained as to what needed to be done to identify the remains.
Mr Kenny said this was one of a number of issues that had been left lying in the shadows for many years.
He had been personally shocked by the revelations from the commission and he said the findings were all the more poignant given the fact that many people would have passed by the location where the remains were found over recent decades.
He commended the work of Tuam historian Catherine Corless, who brought the issue to the fore in recent years.
Mr Kenny said he was glad that the scale of what had happened in Tuam was beginning to come to light.
Labour TD Joan Burton has said that the Catholic Church has to reflect on what it can do to make amends for what happened at former mother and baby homes.
Speaking on RTÉ’s Drivetime, she said the Bon Secours Sisters have questions to ask of themselves, saying the people who are descendants of the women should be paid the respect that they are owed.
She said she was adopted and when in government tried to progress the rights of those who were adopted, but that she felt a "reservation" on the part of some of "official Ireland".
She commended the commission for its work, but said tracing legislation is now essential.
Meanwhile, director of DNA at Forensic Science Ireland Dr Geraldine O'Donnell said any decision to exhume the remains would result in a process that would take a long time and be very costly.
She said there were issues to be agreed for society in general at an ethical level.
If the exhumation went ahead, she said work could be done gathering samples from living relatives.
Asked if it was likely that Forensic Science Ireland would be involved, Dr O'Donnell said the coroner in Galway would make the initial decision, which would then be referred to An Garda Síochána, which might then ask for their assistance.