The Government is expected to announce a move to a mixture of level 4 and level 5 restrictions for the entire country as the number of Covid-19 cases continues to rise.
Considerable differences of opinion remain around how far the Government should now go after the coalition leaders were briefed by Nphet on the recommendation to move to level 5 restrictions.
It comes as 1,283 confirmed cases of Covid-19 were announced on Sunday, while another three people have died with the virus.
One Government source said it is now likely that the Cabinet will settle on the introduction of level 4 restrictions nationwide with some additions. The closure of outdoor dining, as well as a travel limit, are all being considered.
It is understood that most who attended the meetings on Saturday in Government Buildings agreed that the proposal to impose level 5 restrictions for six weeks will not be accepted.
"There is no agreement, but there is certainly a sense that six weeks is too long, it would be very difficult to ask that of people, a shorter period would be more manageable," said a senior government source who attended the briefing.
He added that a four-week period is more likely and the situation would then be reviewed after this time.
Minister for Higher Education Simon Harris confirmed that the Government is to take "decisive" action on Monday, adding that level 3 restrictions "have not worked".
"It's clear now that the virus exists at such a level in all our community, a county-by-county approach would not be sufficient. So we will have to bring in more restrictions. Level 3 has not worked in terms of getting the virus to where we need it to get to," said Mr Harris.
It is understood that Green Party leader Eamon Ryan, Finance Minister Paschal Donohoe and Minister for Public Michael McGrath are in favour of keeping as much of the economy open as possible and not going beyond level 4.
Other considerations, including the impact further restrictions would have on people's mental health, as well as a possible increase in domestic violence are being taken into account.
However, Tánaiste Leo Varadkar was said to be "gung ho" about a move to the strictest of measures.
"The Taoiseach is keen to step up restrictions but has not specially said whether we should go to level 4 or 5," one senior source said.
Those who argued for not moving beyond level 4 restrictions pointed to the fact that the latest measures had only been in place for 12 days and so the full impact had not been felt.
It is understood that Health Minister Stephen Donnelly raised the possibility of introducing a bubble system which has been adopted in New Zealand.
This would allow those living alone and single parent families to "attach" to one other household for social visits.
It would also allow single parents to share childminding duties with another family member or adult.
It is understood that this idea is now under serious consideration and is being further developed ahead of today's Cabinet meeting.
Fine Gael ministers met over zoom yesterday, while Taoiseach Micheál Martin contacted his ministers individually ahead of today's Cabinet meeting.