The Health Service Executive has paused access to the Fair Deal nursing home scheme from the normal placement list, to allow patients occupying hospital beds priority access.
HSE Director General Designate Tony O'Brien said that the scheme was not being suspended or frozen, but that priority was being given to adult discharges from hospital for a two to three-week period.
He also said that as a result of extra places made available earlier in the year, everyone on the Fair Deal placement list was four weeks ahead of where they would have been.
The "exceptional measure" has been approved by Mr O'Brien under the Health Act.
In a letter to Nursing Homes Ireland, the HSE says that in recent weeks there has been significant pressure in some hospital emergency departments.
It says these pressures are being compounded by the number of beds being inappropriately used by patients who require long-term care.
There are also significant risks for the safety of other seriously ill patients presenting in hospital emergency departments who cannot get timely access to appropriate care.
As a result it has been decided "during this period to target the provision of long-term care beds under the scheme to qualifying patients in acute hospitals".
It says that any further extension of the freeze period will have to be formally approved by the director general designate.