Surgeries at a private hospital have been cancelled and about 300 jobs are on the line after it was put into liquidation.
Mount Carmel in south Dublin, which specialises in maternity and non-emergency operations, had been for sale after being put up as security for property loans which were transferred to bad-bank Nama.
The agency said no buyer could be found for the healthcare unit and it was not prepared to continue taking losses on running costs.
The Churchtown hospital is facing an orderly full wind down, the liquidators RSM Farrell Grant Sparks said.
All medical and administrative staff have been told to report for duty as rostered over the coming days and they will be given information on the closure.
Nama said t he hospital has been incurring significant losses since it took over the loans in 2010.
"These losses have been funded by Nama while it has sought, in conjunction with the debtor, to put in place arrangements which would enable the hospital to operate on a viable basis," the agency said.
"Unfortunately, it has not been possible to formulate such arrangements."
There are 328 staff at Mount Carmel including 150 nurses working full-time, another 100 full-time employees and 78 part-time.
Mount Carmel had been on the market for much of last year and into this year and despite lengthy negotiations with various prospective buyers, including health enterprises and agencies, an acceptable price was not going to be achieved, Nama said.
The Department of Health confirmed last month that it was not in the running to buy it.
"Given that Nama's primary objective is to obtain the best possible financial outcome for the taxpayer and given that the sale is not proceeding, Nama has decided that it can no longer continue to fund unsustainable losses at the hospital," Nama said.
Declan Taite and Anne O'Dwyer of RSM Farrell Grant Sparks have been appointed liquidators by the High Court.
In a statement they assured patients booked in for treatment over the next few days and weeks.
"All current patients in the hospital will be fully cared for in Mount Carmel. Obstetrics patients scheduled over the coming days will also be fully cared for in Mount Carmel. All of these patients will be contacted by phone to confirm these arrangements," they said.
"It is envisaged that obstetrics patients who are booked into Mount Carmel for maternity services in the weeks and months ahead will be transferred to alternative maternity hospitals.
"There will be no more elective surgical procedures carried out at the Hospital from today. All of these patients will be contacted by phone to confirm these arrangements."
A helpline, 9am to 5pm, and email facility has been set up to cater for queries from patients on 01 408 6966 and firstname.lastname@example.org.
Kevin Figgis, organiser with trade union Siptu, said: "We are deeply concerned by this move. We will be seeking to explore all possibilities for maintaining the operation of this landmark hospital.
"Our members working at Mount Carmel have always shown great dedication to the care of their patients and this news has been a devastating blow to them.
"Siptu will be seeking to ensure that everything is done to explore all possible avenues to protect the hospital and the jobs associated with it."