The Cabinet will meet tomorrow to discuss the rapid spread of COVID-19 amid a sharp rise in hospital admissions.
There are more people in hospital with coronavirus today than any date since May 15th.
409 patients are in hospital with the virus, which is 49 more than yesterday.
It is significantly more than the peak during the second wave, when 354 people were hospitalised on October 27th.
The Minister for Health Stephen Donnelly confirmed that the unscheduled Cabinet meeting would take place tomorrow to consider advice from NPHET.
It is understood Ministers will consider recommendations from the National Public Health Emergency Team to implement level five restrictions.
Tony O'Brien, the former director-general of the HSE, said today that the number of COVID-19 hospital admissions is very concerning.
He said: "I think they are probably the most concerning leading indicator of the problem we are now facing.
"Obviously, we're all aware of the rapid increase in positive infections being reported by the Department of Health.
"We also know there's a lag between that and hospitalisation so to see both of those heading in the wrong direction at the same time is deeply concerning.
It comes as 79-year-old Dublin grandmother Annie Lynch became the first person in the Republic to get the coronavirus vaccine today.
Minister Donnelly said the first immunisation against the virus here marks "a new and hopeful chapter in our fight against COVID-19" after "the most difficult year for our country".
Beaumont Hospital as well as Cork and Galway University Hospitals will also begin administering vaccines today.
A further 30,000 vaccines are due to arrive in the country this afternoon.