The Irish Blood Transfusion Service (IBTS) is to import blood from the NHS Blood Donation service in England to address a shortage in blood supply.
It said it had a run on the O negative blood supply over the June Bank Holiday weekend and it has not been able to catch up with demand ever since.
The service is importing blood supplies from the UK this week because of a shortage in stocks of negative blood types.
115 units of Rh Negative blood groups - O negative, A negative and B negative - are being collected at the NHS Blood and Transport service in Manchester today.
It is expected to arrive in the early hours of tomorrow morning.
The IBTS said it has not imported blood in bulk since the late 1990s but walk-in clinics for blood donation have been replaced with an appointment-based system due to Covid-19 restrictions which has impacted stocks.
Medical and Scientific Director with the IBTS Dr Stephen Field said only 9% of donors are 0 negative.
"We had to bleed them slightly more frequently than other donors in order to supply the 15% of 0 negatives which were required in hospitals," Dr Field said.
Just 3% of the population donates blood regularly.
The service said it was not unique in facing shortages of blood as many blood services around the world were also reporting shortages.
Dr Field said: "It has been a very tough 15 months for everyone but as hospitals increase their levels of activity, the demand for blood is as great as ever.
"We are urging donors, especially those with Rh Negative blood groups, to make an appointment to give blood over the summer months.
"If you receive a text message from us, please respond to the number provided to make an appointment."
Clinic Nurse Manager at IBTS in D'Olier Street in Dublin Sarah Monaghan said they have noticed a drop in donors coming in as restrictions have lifted.
"At the start of the pandemic we reduced the amount of donors that were able to come into the clinic but other than that our clinic was running as normal. We were able to enforce social distancing at the clinic and able to build up the amount of donors in the clinic. We stopped having walk-ins and made it all appointment based," she said.
Ms Monaghan said Irish people are good at donating blood once they get started as they do always come back.
"We still need the exact same amount of donors coming in. Any regular donors we will be sending them a text and when they get that they can give us a call to make an appointment. Any new donors who are interested in donating we want them to go on the website, get eligibility and then to start donating with us," Ms Monaghan added.
The service said it was not unique in facing shortages of blood as many blood services around the world were also reporting shortages.
Dr Field said: "It has been a very tough 15 months for everyone but as hospitals increase their levels of activity, the demand for blood is as great as ever.
"We are urging donors, especially those with Rh Negative blood groups, to make an appointment to give blood over the summer months.
"If you receive a text message from us, please respond to the number provided to make an appointment."
Anyone who wishes to donate can take an eligibility quiz and register their interest at www.giveblood.ie.
Clinic Nurse Manager at IBTS in D'Olier Street in Dublin Sarah Monaghan said they have noticed a drop in donors coming in as restrictions have lifted.
"At the start of the pandemic we reduced the amount of donors that were able to come into the clinic but other than that our clinic was running as normal. We were able to enforce social distancing at the clinic and able to build up the amount of donors in the clinic. We stopped having walk-ins and made it all appointment based," she said.
Ms Monaghan said Irish people are good at donating blood once they get started as they do always come back.
"We still need the exact same amount of donors coming in. Any regular donors we will be sending them a text and when they get that they can give us a call to make an appointment. Any new donors who are interested in donating we want them to go on the website, get eligibility and then to start donating with us," Ms Monaghan added.
Anyone who wishes to donate can take an eligibility quiz and register their interest at www.giveblood.ie.