Acting Chief Medical Officer Ronan Glynn said that the country's focus "has to be on public health".
Doubt has been cast over whether all pubs will be able to reopen in Ireland on 10 August, following Thursday night's Department of Health briefing.
This comes as the Republic of Ireland recorded 85 new Covid-19 cases on Thursday, the highest daily increase in cases in 10 weeks.
When asked what he would say to pub owners who are concerned whether pubs will be able to open a week from Monday, Glynn said that he was "very sorry" for the position they are in "but our focus here has to be on public health".
He said: "Today's figures demonstrate how quickly Covid-19 can re-emerge in our country.
"We are now at a crucial point in our response to Covid-19. Over the coming days it is vital that everyone continues to avoid large crowds, physically distance, wear face coverings where appropriate and wash hands regularly."
Pubs who can't serve a substantial meal and nightclubs had been due to open from 20 July, but a decision to delay the reopening until 10 August was made a number of weeks ago.
Earlier in the week, the Licensed Vintner's Association said that at least 2,450 Dublin pub have been jobs lost since pubs closed in March.
