People aged 16 and over will be offered a Covid-19 vaccine by the end of September, the Cabinet has heard.
The Government is also examining the possibility of vaccinating those aged 12 to 15 during the autumn.
This is being considered by the National Immunisation Advisory Committee (NIAC).
A decision was also taken by Government to change the rules around PCR tests for children entering the State.
The requirement will not apply to children aged under 12, rather than the previous situation, where all children aged over seven years needed this test when returning to the country.
Government figures are this evening planning on the basis that vaccinated people arriving here from Britain from Monday next will not have to self-quarantine.
Officials have said that the 5 millionth vaccine dose will be administered in Ireland this week, as the roll-out continues across the country.
HSE chief executive Paul Reid has said "we are going to win the race" of the vaccines versus the Delta variant, but warned that "we do have a very risky few weeks ahead".
Today marks 500 days since the first case of Covid-19 was reported in Ireland.
The HSE boss said "500 days is a long time to be dealing with Covid, particularly for our frontline healthcare staff".
He said while there have been many different phases over the last 500 days, "now thankfully we have a very effective vaccination programme, which puts us in a much better place".
So far, 4.8 million Covid vaccines have been administered.
72% of the eligible adult population are partially vaccinated, while 57% are fully vaccinated.
The HSE said it is on course to deliver over 300,000 vaccines to people this week, taking the total administered to more than 5 million doses.