Reopening pubs now could "materially add to the possibility of a second wave" of Covid-19, Health Minister Stephen Donnelly has warned.
He said that while Ireland has been doing well in the fight against coronavirus, there is increasing concern over the rise in the R number.
Health experts say the R value, which is the number of people that a single infection person will go on to infect, is now between 1.2 and 1.8.
On Wednesday, the Government made a decision to delay the reopening of Ireland's pubs and nightclubs until August 10.
Plans to allow larger crowds to gather indoors and outdoors from Monday have also been scrapped amid concerns over the spread of the virus.
Mr Donnelly said if the R number is closer to 1.8, then cases of Covid-19 could rise up to 160 per day in the next three weeks.
"All pubs are being treated the same, that's the public health advice," he said.
"This is not easy. This is not an easy decision to make. We are following the public health guidelines.
"Essentially we prioritising the opening of schools, the opening of healthcare facilities, the opening of the economy over the accelerated reopening of the pubs.
"This is not done lightly. We really do understand that there are publicans all across the country who are waiting and hoping they will be able on Monday.
"It hasn't been done lightly, but the public health advice is, were we to open them now it could materially add to the possibility of a second wave and it's just not a risk we are willing to take."
It was also confirmed that social visits to people's homes will remain limited to a maximum of 10 visitors from no more than four other households.
Restrictions on indoor gatherings to 50 and outdoors to 200 will remain until August 10.
Mr Donnelly said that wearing face coverings in shops and other indoor spaces is advised.
He added: "On the first day on the buses, nine in every 10 passengers arrived with a face mask.
"You can be sure that many of the one in 10 who didn't, some can't wear them, some forgot them.
"So if we continue as we have been, my hope is there will be no need for enforcement whatsoever."
Taoiseach Micheal Martin said on Wednesday that his main priority is to reopen schools in September and then resume non-Covid health services as quickly as possible.
"If we did not intervene and take these measures, it would take an inevitable course, which is in nobody's interest," he added.
Pubs that serve food can continue to serve alcohol with a substantial meal.
Acting chief medical officer Dr Ronan Glynn said the number of cases had increased over recent days and expressed concern about the number of contacts for some individuals and the development of infection clusters.
He added: "It is a pause.
"Compared to many countries around the world, we are still in a good position. The challenge is to maintain that good position and ensure that the good work over many months is not lost.
"This virus is extremely infectious. It wants to spread but it needs people to come into contact with each other to do so."
Ireland's Covid-19 death toll rose to 1,748 after the deaths of two more people were confirmed by the National Public Health Emergency Team.
As of midnight on Tuesday, the health system had been notified of 14 more confirmed cases.
