The government is awaiting a decision as early as this evening on the use of the Johnson and Johnson vaccine.
It comes as Ministers prepare to make decisions on the re-opening of the country over the next few months.
NPHET cancelled its usual Monday press briefing today, instead waiting to give its opinion on the current situation until later in the week.
Health officials will meet on Wednesday morning to provide recommendations to cabinet, ahead of a final sign off on Thursday.
Click and collect, construction, retail, barbers and hairdressers, religious services and outdoor sports training are the areas being examined for May re-openings.
Separately the National Immunisation Advisory Committee is finalising its recommendations on the use of the Johnson and Johnson vaccine.
Government sources expect it to be delivered either this evening or tomorrow morning.
The recommendation will first go to Chief Medical Officer Dr Tony Holohan, who'll inform Health Minister Stephen Donnelly.
After government makes its decision it will then be up to the HSE to implement its roll-out.
The hope in government circles is any restriction on the use of the vaccine due to the risk of rare blood clots will be more limited than the advice around the AstraZeneca vaccine, which could still see Johnson and Johnson widely used here.
