Some 30,000 people due to receive the AstraZeneca Covid-19 jab this week will have their vaccinations rescheduled in the next few weeks, the Health Minister has said.
Stephen Donnelly said he hopes most of the people whose vaccines are being deferred will receive their first dose by the end of the month without affecting the rollout of vaccine to other people.
Use of the jab was suspended on Sunday as a precaution after reports of serious clotting in adults in Norway which left four people in hospital.
Mr Donnelly said he understood that people were naturally "disappointed" by the deferral of their appointments but that the National Immunisation Advisory Committee (NIAC) and the Health Products Regulatory Authority (HPRA) had acted "decisively and quickly" in response to new information late on Saturday night about the Norway cases.
He added that he had no hesitancy in temporarily suspending use of the AstraZeneca jab and that he hopes it will only be for a short period.
Mr Donnelly told RTÉ Radio 1's Morning Ireland programme: "Hopefully the 30,000 for this week will be rescheduled very, very quickly.
"We should be able to reschedule them and in so doing, not have to delay other people. So in other words, do the 30,000 at the same time as people who we were planning on doing in the coming weeks as well."
Mr Donnelly defended the State's vaccination programme, highlighting that 99% of people over the age of 85 have received their first dose of a coronavirus vaccine within a three-week period as planned.
"The vast majority of the target groups for the GPs are being done," he said.
"For example the group 85 and older, there was a three-week period for the GPs to vaccinate that group.
"And there was understandably some focus on some of the things that didn't work which is absolutely fair and lessons needed to be learned, but within that three weeks 99% of that cohort were still vaccinated."
The minister added that at present 95% of the vaccines arriving into the country were being administered within seven days.
Speaking on the same programme HSE chief executive Paul Reid acknowledged the temporary suspension of the AstraZeneca vaccine was "disappointing" for those due to get jab.
But he said the decision was made to ensure the continued rollout of the vaccination programme in a "safe way".
"We all expect and hope that it is a very short pause," Mr Reid said.
"We know the European Medicines Agency has established a committee looking at the data all across the world.
"We know our own Health Products Regulatory Authority are a member of that committee and will be involved in the assessment throughout this week.
"I think it does enhance and continue our strong reputation of progressing cautiously."
But Mr Reid said people over the age of 70 will continue to be vaccinated this week.
"Our overall vaccination programme across the over-70s is progressing really well," he said.
"Over 130,000 vaccinated already. Another 50,000 will be vaccinated this week.
"So despite the issues that we have in AstraZeneca this week, a very good programme continues."
Over the weekend, 250 housebound people over the age of 70 were vaccinated in their homes through the National Ambulance Service.
Mr Reid added that the rollout of the vaccination programme would "step up" in the second quarter of the year.