The Irish health service expects to spend tens of millions of euros rebuilding its IT systems from a cyberattack which is set to cause significant disruption to diagnostic services into next week.

Ireland's health service operator shut down all its IT systems Friday to protect them from a significant ransomware attack the government said was carried out by an international cyber crime gang.

While the COVID-19 vaccination program was not directly affected and the Health Service Executive (HSE) restored its test and tracing system within hours, hospital appointments have been cancelled across all outpatient services.