The Irish Blood Transfusion Service says it urgently needs more donations.
The body is renewing its appeal today saying the good weather has led to a drop in visitors to its clinics around the country.
The IBTS has said it needs 15,000 donations by the end of this month.
Director Paul McKinney has said it is a difficult time for them.
“Obviously with the good weather, which actually does impact on people attending our clinics, combined with the start of the European Championships and indeed with the Olympics starting in August, we do find it very difficult to sustain the blood supply over the summer months,” said McKinney.
“That’s why we are launching this promotion for the week to ask donors to attend clinics.”