The Department of Health has been notified of 50 additional cases of Covid-19 and no new deaths.
The number of Covid-19-related deaths in Ireland remains at 1,763, while the total number of confirmed cases has risen to 26,303.
In a statement the National Public Health Emergency Team says that of the new cases identified, 31 are men and 19 are women. 81% of the new cases are under 45 years of age.
NPHET says that 42 of the cases are associated with outbreaks or are close contacts of a confirmed case. It says that four of the cases have been identified as community transmission.
Eleven of the new cases were located in Wexford, while ten were identified in Kildare, six in Dublin, five in Donegal and 18 are spread across nine other counties.
The Acting Chief Medical Officer has said that the focus will be continuing every effort to slow the spread of the coronavirus.
Dr Ronan Glynn said: "I know the decision yesterday not to move to Phase 4 will have been disappointing for many. However, NPHET's priority must be to control the spread of this virus in our communities and to protect the progress that we have achieved to date.
"Our focus over the coming weeks will be on continuing every effort to slow the spread of the virus so that our schools can reopen, our healthcare services resume, and our nursing homes are protected."
The Government earlier published the advice it received from NPHET, which led to its decision yesterday not to go ahead with Phase 4 of the reopening roadmap.
The advice is set out in a letter from Dr Glynn to Minister for Health Stephen Donnelly.
In it, Dr Glynn says NPHET has "significant and growing concerns".
These include the increasing number of cases being reported each day as well as increasing numbers of cases in vulnerable groups such as those living in direct provision.
He said NPHET is also concerned about multiple significant outbreaks in workplaces - particularly in construction and food production sectors; the increasing number of cases in young people, particularly those between 25 and 34 years old and the shift in the location of the majority of cases from the greater Dublin region to other counties in the last seven to ten days.
The Minister for Health has said he understands the frustrations of those impacted by the delay to Phase 4 of the lifting of Covid-19 restrictions, but said the decision was made to avoid another lockdown scenario.
Stephen Donnelly said the rise in the number of confirmed cases of Covid-19 was being driven by clusters of cases all around the country and eight of these clusters were "quite significant".
Speaking on RTÉ's Morning Ireland, Mr Donnelly said Covid-19 is spreading at a fast rate around the world, and the five-day average cases in Ireland has jumped from fewer than 10 to over 50 recently.
He said the National Public Health Emergency Team is unanimous and unambiguously of the view that things are "very, very finely balanced" and the Government decided to take a cautious approach.
Meanwhile, the number of people with Covid-19 in hospitals around the country has risen slightly.
There are 15 patients with confirmed cases of Covid-19 in hospital - five are in intensive care.
This compares to last Thursday when numbers in hospital were at their lowest level since the peak of the pandemic in April.
On that day, there were six positive cases in hospital and four in ICU.
There are three positive cases in Tallaght University Hospital, two in Drogheda, two in the Mater, two in Wexford and one each in Beaumont, Cavan, Galway, Kilkenny, Mullingar and Limerick hospitals.
There are 112 patients in hospital with suspected Covid-19, again spread all across the country, with the most suspected cases in Limerick where there are 26 patients with suspected Covid-19.
Eight patients with suspected Covid-19 are in ICU.
There were no deaths in ICU in the previous 24 hours.
The number of people in hospital and in intensive care is one of the signs public health officials watch carefully when monitoring the spread of the virus.
Other data shows that as of midnight on Sunday, cases have risen significantly in Kildare, which has seen an extra 15 cases, and Clare, with eight new cases.
Laois also had eight new cases between Saturday and Sunday and Offaly saw five new cases.
Community transmission accounts for just over 31% of cases, close contact with a confirmed case accounts for two thirds of cases, and travel abroad accounts for just 2.5% of cases.
Ten more positive cases of coronavirus have been detected in Northern Ireland, the Department of Health has said.
The total number of people who have been infected is now 6,006.
No new deaths were recorded, leaving the total in Northern Ireland at 556, according to official figures.
Elsewhere, the Scottish government has reintroduced lockdown rules in the city of Aberdeen, after a number of Covid-19 clusters were discovered there.