Government party leaders Taoiseach Micheál Martin, Tánaiste Leo Varadkar and Minister for Transport Eamon Ryan will meet the chief medical officer (CMO) Dr Tony Holohan today to discuss the shocking recommendation which would see the vast majority of counties moved from Level 2 to Level 5.
Fianna Fáil TD Jim Callaghan says moving to Level 5 is "completely disproportionate" and says we need to "recognise" more people are going to die.
"We've got to recognise that this having a terrible impact on young people in this country," he said.
"We also have to recognise that, predominantly, young people aren't affected by it. The median age of the dead was in the late 80s.
"They also informed the committee that 90% of people have died with had underlying conditions.
"You've got to look at young people out there who aren't in their late 80s, who don't have underlying condition and been told about their education, their employment, their entertainment, their socialisation, their intimate relationships, all of these things have to stop. We're telling them that - that's not sustainable. We need to recognise that this is a very difficult disease and that more people are going to die from it.
"I'm concerned that the manner by which we're doing business at present, it's not a good idea for the people of Ireland to hear this on a Sunday evening, a leak from NPHET and an indication that there's a recommendation that the country is going to go to level 5. We shouldn't be doing business this way."
Simon Harris, formerly the health minister, tweeted early on Monday morning to say that "clarity" is needed. A full cabinet meeting is not due until Tuesday.
Former cabinet minister Barry Cowen also took to social media to say: "If we’re brutally honest, as a people we could better adhere to existing restrictions as they stand. Let’s collectively put that right rather than going nuclear just yet."
It is understood many TDs have already informed government ministers of their fears the effect Level 5 would have on the economy and business.
It has been speculated that the swift jump has been linked to the rise in hospital admissions over the weekend. Ireland has the lowest bed capacity in Europe and there have been concerns services could be overwhelmed.
NPHET's recommendations for up to four weeks of lockdown would mean no visitors to homes, no social gatherings, no sporting matches, the closure of all pubs and restaurants except for takeaways, the closure of gyms, and severe restrictions on the numbers that can attend weddings and funerals.
A 5km travel limit for exercise would also be imposed, but the restrictions would not necessarily mean the closure of schools.
Tipperary TD Mattie McGrath says NPHET must be held to account for extreme recommendations causing huge uncertainty.
Mr McGrath has slammed NPHET for "the irresponsible manner in which they have leaked their recommendations" and said that such news is detrimental to the business community and wider society and has called on NPHET to be held to account for the damage that this extreme announcement will have.
"It is exactly this type of scenario that we were supposed to avoid by having the Living with Covid plan to ensure that Business and society could operate effectively with restrictions and plan ahead as we move gradually through the different levels," he said.
“We are all concerned about the rise in cases in recent weeks but we have to be cognisant of the impact of taking such an extreme measure with limited justification. There is little point in having a road map with stages laid out if we are going to scrap it and jump to the most extreme level just weeks after introducing it without moving gradually through the stages.”
Meanwhile, the GAA has suspended all club games with immediate effect.
The GAA’s Management Committee has released a statement saying that "all GAA Club games at all levels" are suspended with immediate effect and until further notice.
It said the decision has been taken in the interests of public safety following a number of incidents that it said had been brought to its attention in recent days.
It singled out post-match celebrations and a lack of social distancing at certain events, which it said had proved disappointing and problematic.
This directive applies to all ages and all grades across the island - clubs, social centres and bars have to close, but training will continue to be permitted, it said.
The GAA's move comes in the wake of several apparent breaches of public health guidelines linked to matches and celebrations and follows the widespread shock at Sunday's NPHET recommendation to move the entire country in Level 5.