The cost of the cyber attack on the Health Service Executive (HSE) IT systems could rise to half a billion euro.
CEO of the HSE, Paul Reid, said that the immediate cost of the attack amounted to over €100 million.
However, Reid said that this figure will rise substantially when other figures are implemented.
Fine Gael Senator Martin Conway said that he would expect the overall figure to rise to half a billion euro.
Paul Reid confirmed that Conway was correct, adding that substantial investment is needed to protect the systems.
Reid continued to say that investment is needed in upgrading the IT systems, and funding will need to be made available to put a security operation centre in place to deal with future attacks.
He went on to warn that the HSE may not have seen the worst of the cyber attack yet.