The Government ignored NPHET advice on a couple of key issues in Ireland's roadmap for reopening.
That's according to Tánaiste Leo Varadkar.
The full roadmap saw all major restrictions being lifted by October 22, with the first wave of major changes occurring on September 6.
However, there is one big difference coming into effect on Wednesday.
Public transport will see 100% capacity for the first time in over a year - but Mr Varadkar refused to confirm that NPHET had signed off on the move when appearing on RTE Prime Time on Tuesday evening.
Speaking on the show, Mr Varadkar had the following to say about the group and the decisions made by Cabinet.
"The decisions were run by public health officials last Friday and finished on Monday. What we're proposing is not exactly the same as what was recommended by NPHET but in the same kind of line.
"Of course, October 22 is dependent on achieving certain milestones like 90% of adults fully vaccinated and then two weeks after that, plus the modelling from NPHET suggests we're beyond the peak of the Delta wave at that point.
"When it comes to the easing on the 6th and 20th, NPHET was happy with us opening indoor services to fully vaccinated, but they didn't like the idea of people under 18 not vaccinated being let in.
"Similar to hospitality, NPHET was favourable to us opening to fully vaccinated, they didn't want unvaccinated under 18s being let in. What they say in their advice is that in the run up to October 22, there may be a new variant, or the hospitals could be in bad shape."
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And when host Sarah McInerney turned the conversation onto public transport, Mr Varadkar refused to confirm that Dr Tony Holohan, the Chief Medical Officer, had signed off on the decision.
"All of these were discussed, but NPHET is made up of 40 members. There are lots of conversations which happen in the meetings. The reason we're going back to full public transport is because we have a lot of people vaccinated and with people attending work and school we found it appropriate. NPHET did not give specific advice on that.
"I'm sure NPHET would have the same concerns as we would have with going back to full capacity."
Taoiseach Micheal Martin addressed the nation on Tuesday where he outlined a full plan for the removal of Covid-19 restrictions in the coming weeks and months.
October 22 has been earmarked as the day which will see the end of all legal restrictions on society and the economy with a major reopening expected.
Nightclubs, restaurants and bars will all finally be freed from restrictions to service while public transport will return to full capacity.
Live music sporting events are also set to get the go-ahead with added capacity while new advice on masks and social distancing are set to be adopted.
