Health Minister Stephen Donnelly has rowed back on expectations that everyone in the country will be vaccinated by September.
Mr Donnelly had said the Government is planning its vaccine programme around a supply of vaccines that "would mean every citizen can be vaccinated by September".
However, speaking in the Dáil yesterday, he said this roll-out was "heavily caveated" on supply of the vaccines.
There has been disruption in supplies with the Pfizer/BioNTech vaccine, and now doubts have been cast on the delivery of AstraZeneca doses.
The minister previously promised 700,000 people would be vaccinated by the end of March.
"The figure of 700,000 was in an effort to provide an indicative target for the Oireachtas," Mr Donnelly said.
The latest figures show that 147,700 Covid-19 first doses have been administered, and 13,800 people have received their second dose. Under the plans, vaccination of over-70s will start next month.
"The figure of 700,000 was conditional on supply coming in, including from AstraZeneca, and as we're all aware, AstraZeneca have signalled that they will be not delivering the full amount that was anticipated," Mr Donnelly said.
Meanwhile, the Joint Committee on Health will today receive an update from the High-Level Taskforce on Covid-19 vaccination at a meeting in Leinster House.
Chairman of the Committee Deputy Seán Crowe said: "Vaccines offer hope, for an end to lockdown and hopefully one day an end to this pandemic which has now bereaved more than 3,000 families and caused ill-health, fear and disruption for so many across the State."
He said people want to know the exact details of when the vaccine will be available to them and their loved ones.