The Irish Nurses and Midwives' Organisation has said the €74m provided to implement measures under the Emergency Department Task Force report will not solve the problem.
Speaking at the start of its three day annual conference, in Trim Co Meath, INMO General Secretary Liam Doran said the extra funding was welcome but much more is needed.
He said today's new INMO trolley figures covering January-April, which show a worsening situation; predate the EWTF report funding measures.
Mr Doran said the union would be looking to see the overcrowding figures from May to June to establish if there is any improvement.
He also said nurses and midwives will be seeking a restoration of a 37 hour week, as well as a significant first step in pay restoration.
Minister for Health Leo Varadkar is due to address the meeting on Friday.
Earlier, the INMO said that new figures showing an increase in the numbers of people on hospital trolleys is very worrying.
The union says patients were on trolleys 35,135 times at some stage during the period from January to April of this year - an increase of 26% on the same period last last year.
Speaking on RTÉ’s Morning Ireland, spokesperson Phil Ni Sheaghdha, said the problem was also worsening outside of the capital.
She said: "We have an increasing phenomenon now outside of Dublin, which is very worrying.
"If you look at hospitals in the midlands, their figures have gone from a figure of 12 in 2006 to 806 people for whom there aren't beds in the month of April 2015.
"So that's a significant shortage of beds contained in that figure."
She said until there was investment in beds the problem would continue, pointing out that for every thousand people in Ireland there are fewer beds than the European average - four per thousand compared to 5.2 per thousand.
Ms Ni Sheaghdha said the Government's task force had focused funding on long-term patients inappropriately placed in acute hospitals but she said if all of these patients were discharged tomorrow there would still be a problem due to the lack of acute beds.
She said there was also a compounding problem of recruiting nurses. She said two hospitals had gone to India this week to recruit staff.
Ms Ni Sheaghdha said they had asked the Minister for Health to look at incentives to attract people to work in the nursing sector.
There are 465 patients on trolleys or on wards today waiting for admission to a bed.
Figures from the INMO show Beaumont Hospital has the largest number with 47 patients waiting, there are 41 waiting at Our Lady of Lourdes Hospital in Drogheda and 39 waiting at the Mater in Dublin.