The Taoiseach says it's expected that COVID-19 cases will continue to rise in the coming weeks.
Micheál Martin says Ireland has not yet reached the peak of the current Delta wave of infections.
It comes as 2,125 new cases of the virus were recorded yesterday - the third time in a week the figure has been over 2,000.
259 patients with the virus are in hospital, including 54 in intensive care.
Chief Medical Officer Dr Tony Holohan said the current level of transmission is of "significant concern".
The number of newly confirmed #COVID19 cases in hospital in the last 24 hours has reached a level not seen since mid-February.
This upward trend in serious infection is of significant concern, increasing the pressure on frontline healthcare services and non-COVID care.
— Dr Tony Holohan (@CMOIreland) August 21, 2021
Taoiseach Micheal Martin says the increase in case numbers is something that was anticipated by health officials.
He said: “We have not reached the peak of the Delta wave yet, and of course any time the disease is increasing at this rate is a time of concern.
“I’d appeal to people to watch the fundamentals in terms of social distancing, wearing masks indoors in particular, and adhering to the basic guidelines.”
He said vaccination is the key, but noted that many people in younger age groups still aren’t fully vaccinated.
NPHET’s Professor Philip Nolan yesterday said Ireland will see the full effects of the vaccine programme "through August and into September", and case numbers should "stabilise".
While over 84% of adults have now received both doses, it takes 7-14 days after the second dose for someone to be considered fully vaccinated.