There are more than 580 patients requiring admission to hospital waiting on trolleys in emergency departments or on wards for a bed on Tuesday, nurses have said.
The Irish Nurses and Midwives Organisation said the hospitals worst affected by overcrowding were Cork University Hospital, Letterkenny University Hospital and University Hospital Limerick.
The INMO said there were 583 admitted patients waiting for beds on Tuesday morning.
This represents an increase on the figures recorded on Monday when there were 541 patients queuing for a bed.
Minister for Health Simon Harris on Monday acknowledged the number of patients waiting for hospital beds had increased but maintained the numbers were still lower than those recorded at the same period last year.
He said the surge in the number of patients presenting had been forecast and attributed the rise in part to the onset of flu in the community.
The INMO said there were 61 patients waiting for a bed at Cork University Hospital and 43 in Letterkenny and Limerick.
