The Government aims to get all children back to school full-time in late August or September by working on "bespoke solutions", according to the Taoiseach.
The full-time return to the classroom will come without the strict observation of social distancing guidelines.
The full details have yet to be worked out, but hygiene considerations will be paramount, with handwashing and very strict safety protocols.
Leo Varadkar gave the example of the early years sector, where social distancing only applies to adults and not children.
Speaking at a post-Cabinet briefing, Mr Varadkar said: "We're going to come up with a solution that allows all kids to return to school at the end of August, early September as originally indicated."
If the two-metre rule is still in place in September then almost all primary school children will only be able to attend school one day per week, according to the road map published today as guidance for schools.
The two-metre restriction would allow most second-level students to return for just two days per week, according to the document.
The guidelines say the impact of such a requirement on student's education and well-being would be "most extreme".
Mr Varadkar said: "I know there is some concern among parents about the document, which outlines the consequences of applying the two-metre rule in schools as opposed to the one-metre rule in schools.
"I do want to reassure parents, many of whom I know are very worried about what is going to happen at the end of August and in September, what we are working on is being in a position so that all kids can go back full-time.
"We know the difficulties that arise from a two-metre rule. We know the difficulties that arise from a one-metre rule.
"It is all laid out now in black and white, but we also know that we can come up with bespoke solutions in particular circumstances."
If the restriction is reduced to one metre then almost all primary school pupils would be able to attend school for two-and-a-half days per week, the document said.
Some year groups at second level would be able to attend 50% of the time, with other year groups attending at or near a full-time basis.
Taoiseach Leo Varadkar says the government is working on getting all children back to school full-time in late August or September by working on "bespoke solutions" | Live updates: https://t.co/MwB07XWY9Y pic.twitter.com/7N6cE1I4bZ— RTÉ News (@rtenews) June 12, 2020
Minister for Education Joe McHugh said he did not want to envisage a situation where we continue to leave children behind.
He said the Government had to weigh the risk associated with a failure to provide children with education against other public health considerations.
Mr McHugh said this aim of a full return to school was not in conflict with what has been done to date to combat the coronavirus.
He said the Government was very conscious that there could be a resurgence of the virus.
He said that was why there would be very strict safety protocols in schools, to deal with instances such as a child presenting at school with a temperature.
Mr McHugh said his department would continue to work to see what will work best.
He said the protocols his department would draw up would also govern the delivery of the summer programmes, the details of which were also announced today.
"Children will be left behind further if we don't look at a full return to school," he said. "But equally it has to be safe for teachers and pupils".
Education minister Joe McHugh has said it is the Government's view that every student should return to class by September. Speaking this evening he said public health considerations had to be balanced against questions of regression, continuity of learning and gaps in education pic.twitter.com/xMVtGkCmlS— RTÉ News (@rtenews) June 12, 2020
The document states that a 50:50 blended school/home learning scenario would have "very serious impacts to the delivery of meaningful education".
The guidelines say the physical size of the country's schools, and the number of individual classrooms within them represent the most significant constraint to achieve a physical distance between students in the classroom.
It says that teacher supply will be a significant consideration.
It says it is not feasible "from a cost, sustainability, or delivery perspective", to identify and implement the additional classroom capacity that would be needed to accommodate more children.
It says it is also not feasible to consider the wholesale splitting of classes and recruiting of extra teachers, given that there are significant teacher supply issues currently.
Unions express concern about plans
The ASTI teachers union said it "would be very concerned if a differentiated approach to physical distancing is introduced for schools which deviates from that which pertains to wider society".
"Any deviation from the health advice available from the National Public Health Emergency Team would be unacceptable."
TUI President Seamus Lahart said the guidance issued today for schools was "excessively speculative and pays insufficient attention to public health advice".
He added: "The oblique suggestion that classrooms could operate without social distancing is both odd and alarming.
"Classrooms are workplaces, crowded ones at that. These workplaces cannot be treated as if they enjoy some magical immunity from the risk that characterises other workplaces."
The INTO said that any "orderly and safe reopening of our schools any decisions must be led by public health advice".
INTO General Secretary John Boyle said: "We are demanding clear and practical support for schools to ensure a safe environment for both staff and pupils.
"Priority must be given to measures which support the safety and physical/mental health and wellbeing of staff, pupils and parents in primary schools."
Fórsa's head of education Andy Pike said: "The minister says he wants things to return to normal and appears to be content to ignore public health advice.
"We all want to see schools re-open and resume their normal daily routines, but this is not possible at the moment.
"All the available evidence suggests that new measures will be needed to maintain health and safety in our schools whenever they open, be it in July or at the end of August. The minister can’t ignore that fact."
Sinn Féin's education spokesperson has said schools and parents would be "more confused than ever" after today's publication of a study of the options available on the return to school for children.
Speaking on RTÉ's Drivetime, Donnchadh Ó Laoghaire said schools have been operating in a "communication vacuum" and have been unable to begin any planning for reopening schools.
He said: "For any of the schools that I have spoken to they have had no communication with the Department of Education on the issue of reopening. That is unacceptable. It has put them in an impossible situation.
"I know two secondary schools that were planning on different basis - one on two-metre social distancing and one with no social distancing, that was due to the vacuum that was created by the department.
"The vacuum continues, because on the one hand they're outlining the ... planning of two metres and one metre, and then on the other hand saying 'that is not acceptable and we will come back to you in a fortnight with a plan'. That's very unfair to parents. It is a mess."