The Irish Nurses and Midwives Organisation has expressed concern that if support staff are not replaced in the health service, it could have consequences for the workload of its members.
Yesterday, the Government announced a one-off early retirement and redundancy scheme that could see up to 5,000 administration, clerical and support staff leaving the Health Service Executive by the end of the year.
INMO's General Secretary Liam Doran said nurses and midwives would not fill the gaps as their workload was already excessive.
He said the recruitment moratorium for nursing grades must now be lifted.
In the Dáil, Labour leader Eamon Gilmore said the Health Minister's announcement on the scheme had been a while coming.
The Taoiseach said the scheme arises as the Government tries to protect frontline services.
Deputy Gilmore asked if it was practical to try to implement the scheme in such a small time scale.
He wanted to know if 19 November and 30 December were the ultimate dates.
The Taoiseach agreed it was a challenging time scale, but that it should be possible to do without affecting frontline services.
He said centralisation had helped by making it possible for fewer people to administer the scheme.
Speaking on RTÉ's Morning Ireland, a senior official with the IMPACT union, Louise O'Donnell, said she could appreciate the need for savings, but criticised the proposed timetable.
She said employees who might be affected had to look into their entitlements.
Unions representing HSE workers are continuing to assess the practicalities involved in the programme announced yesterday.
The €400m plan would fund around 5,000 staff leaving the HSE.
The HSE wants the staff to leave voluntarily by the end of the year.
Those interested must apply for the scheme by 19 November.
Staff taking the voluntary redundancy package will get three weeks of pay per year of service, capped at two years' salary, plus their statutory entitlements.
The HSE has 17,000 clerical and administrative grade staff and 11,000 support staff.
SIPTU expressed concern that the HSE did not seem to have any plan for dealing with the consequences of taking so many jobs out of the system in the timescale envisaged.
IMPACT said it would challenge the terms of the package being offered and will probably refer the issue to a third-party.
It says the timescales are very tight, and this type of decision on whether to take redundancy or early retirement required people to have more than a two-week period to decide.
