Tanaiste Leo Varadkar has said cases are "likely" to rise in the coming weeks with another lockdown not being ruled out.
The Fine Gael leader said that with people mixing again it is almost a given that daily case numbers will begin to rise.
Speaking on Morning Ireland, Mr Varadkar said: "We have never ruled out the possibility that we would need to reintroduce restrictions for a short period in January."
But when asked if a third lockdown would be necessary, the Tanaiste added: "That’ll have to be decided at the time, depending on what the numbers look like."
In a letter to the Government, The National Public Health Emergency Team has warned government that a “major increase” in socialisation could see 450 infection cases daily being diagnosed before the end of the month.
Taoiseach Micháel Martin has said he does not anticipate new restrictions before the festive period and added that this guide threshold figure was “very arbitrary.”
In a letter to government last week, NPHET claimed that it would be possible to suppress the spread of the virus with a 21 day intervention, but only if it begins as case numbers near 400 a day.
NPHET warned Health Minister Stephen Donnelly that a notable increase in socialising and the diversity of contacts over the festive period could “lead to much higher levels of viral transmission than have been seen to date”.
The emergency team’s modelling shows that if the R number, which estimates how quickly the disease is spreading through the population, grows to 2.0 from December 22 to January 6, between 300 and 450 cases per day could be seen by New Year’s Day, and 800 to 1,200 per day by the second week of January.
