The Tanaiste has signalled that NPHET is likely to recommend the imposition of further Covid restrictions before Christmas following their meeting on Thursday.
Leo Varadkar believes that three areas will likely be subject to further rules in response to the Omicron variant.
The new strain of coronavirus is expected to become dominant in Ireland as soon as next week, with 14% of all infections now due to the variant.
Public health officials including the Chief Medical Officer Dr Tony Holohan will hold crunch talks on whether additional measures should be implemented.
They will then issue these recommendations to government who will decide whether these advisories should be introduced.
While no Cabinet meeting has been scheduled as yet, Mr Varadkar expects the public will be given greater certainty on Christmas restrictions before the weekend.
The Fine Gael leader, along with Taoiseach Micheal Martin and Green Party leader Eamon Ryan, met with NPHET members including Professor Philip Nolan and Dr Holohan on Tuesday night.
Mr Varadkar said the meeting was "routine" and it wasn't about making any decisions, rather it was about meeting Prof Nolan and Dr Holohan to get their assessment on "where we stand in relation to the current Delta wave and the forthcoming Omicron wave".
The next step is for NPHET to meet on Thursday and the Tanaiste expects health chiefs to make recommendations that will subsequently be considered by government.
"I would expect on Thursday there will be recommendations around the management of close contacts, some recommendations designed to decrease the amount of social mixing, and also some recommendations around international travel," he told Pat Kenny on Newstalk.
"When it comes to international travel, it's a slightly different approach. The restrictions we brought in a few weeks ago in relation to international travel were designed to slow the arrival of the Omicron variant in Ireland.
"It has now arrived and as the WHO rightly has said travel restrictions are of limited benefit, so I would expect to see recommendations in those three areas."
Mr Varadkar said he was not going to speculate about what further measures might be recommended, particularly when it comes to the rules around hospitality.
Asked whether Ireland was faring much better than the UK when it comes to Covid-19, he said: "We are in a slightly better situation than they are because our restrictions have been a little bit tighter than theirs, albeit regrettably but necessarily so.
"We're going into this Omicron wave in a somewhat better situation than they are in terms of the numbers in hospital and ICU and also we've had greater use of the mRNA vaccines than they have.
"However, they are ahead of us in terms of the booster doses so we have about 25% of the population done now, about 1.2 million which is a lot and we need to accelerate that over the next few weeks."
He said Ireland is in "a strange situation" and not one "we expected to be in even a few weeks ago".
"We're winning the battle against the Delta wave, the number of people in hospital peaked a few weeks ago around 680, it's around 500 now, 450 last night, and the number in ICU peaked at 130, it's falling now," he said.
"We're doing better than that most optimistic model so we were winning the fight against the Delta wave and that was down to the fact that the third dose programme is going so well, the fact that the public responded to the public health advice and we reduced our contacts and also a natural degree of immunity building up as a result of exposure.
"Things were going well, and even in that school age group, the number of cases is falling.
"The problem is the thing we hoped wouldn't happen for a very long time is that there is a new variant in the world, the Omicron variant, and that is likely to cause an additional wave of infection in the next couple of weeks.
"That has required us to change tack again which is frustrating, depressing, disappointing but unfortunately necessary because the priority has to be to protect people's lives and make sure our health services aren't overwhelmed in the weeks ahead."
Mr Varadkar also explained that there is no specific number when it comes to the proportion of cases linked to Omicron which would mean further restrictions would be introduced.
"The expectation based on South Africa, what's happening in London, what's happened in Denmark and Norway, is that the Omicron variant will be dominant in Ireland as soon as next week and maybe even before Christmas," he said.
"It's never the case that when it comes to making decisions, that there's a magic number that triggers a decision, you have to take into account lots of different factors.
"Unfortunately when it comes to Omicron, there's a lot of uncertainty, it does appear that it is more transmissible than the Delta variant, it seems it has a growth advantage, in part because there's partial vaccine escape.
"There is evidence from South Africa that it is less severe, that you're less likely to become hospitalised as a result of it.
"We don't know whether that's because of the inherent properties or because the immunity has been built up from the other variants' help."
The Tanaiste cited his main concerns around the data emerging about the Omicron variant that is here "on top of the Delta wave".
"The problem is, and I know this sounds a bit strange, if it's twice as transmissible but half as severe, that's still as bad as terms of the impact on the health service," he said.
He added that Ireland needs to double down on the public health measures and speed up the booster programme.
He expects that 1.75 million will have received their extra jab by Christmas and 2 million will have got the additional shot by the new year.
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