The Government has established a “war room” in response to the “very serious” cyber attacks on the HSE and the Department of Health, Minister Simon Coveney has said.
The HSE was hit on Friday by a ransomware attack, with its systems remaining "significantly compromised" two days later, according to HSE chief operations officer Anne O'Connor.
It has also been confirmed that the Department of Health has shut down its systems after finding a similar digital note to that which was found on the HSE's systems.
Speaking on Sunday, Mr Coveney said no one should seek to downplay the potential impact of this attack.
He said many agencies from across the State are involved with the National Cyber Security Centre including the departments of Justice, Defence, Communications as well as An Garda Siochana and the Defence Forces.
The authorities are liaising with Interpol, the European police agency, the Minister for Foreign Defence added.
Mr Coveney said the Government is not talking to the criminals involved in the attack.
“What has happened here is that right across our HSE health care system, malware has been inserted across the network in multiple locations."
Speaking to RTÉ radio, Mr Coveney said it's going to take "quite some time, to clean that data, piece by piece, and to try to back up and protect as much of the data as we possibly can."
Meanwhile, chief whip Jack Chambers said the Government has to strengthen its cybersecurity capabilities in the wake of Friday’s cyberattack on the HSE and on the Department of Health.
Mr Chambers said the Government and its agencies are working through this methodically with the experts that are involved to try and restore the HSE’s IT infrastructure.
“We have to get our diagnostics back and get health care to service delivery restored as quickly as possible, and so much in terms of outpatient appointments and therapeutics have been affected,” Mr Chambers said.
He said everything is being done using our domestic resources and international expertise to respond so that authorities get healthcare service delivery back.
He said the immediate priority is that people can have basic diagnostics and get their appointments back as soon as possible.
But responding to evidence that cybersecurity is chronically underfunded in Ireland, Mr Chambers said the state has to strengthen the provision of cybersecurity.
The HSE is only spending €2m a year on cybersecurity when it is estimated it should be really spending about €36m.
“It is a serious 21st-century threat, both to states and private sector organisations across the board,” he said.
"This is a future threat for everybody.
"Unfortunately, criminals or other state actors can attack the state or other organisations from behind computer screens, and this is a reminder of having to strengthen that.
"We're going to invest in that, and strengthen the National Cybersecurity Centre,” Mr Chamber said on RTÉ’s.
Mr Chambers said all steps will have to be taken to mitigate risks for the Department of Health, "or any other Department where risk has been identified."
Independent TD Cathal Berry said Ireland effectively has no offensive cyber capability at all really.
Sinn Féin’s Louise O’Reilly said that under no circumstances should ransom be paid to the hackers.
“But what I do think this is doubly unfortunate because it comes in the same week as we see an announcement that there are 900,000 people awaiting appointments,” Ms O'Reilly said.
"What we want to see from the HSE and indeed from the government is not just that they can get to the root of the cause of this particular issue because this is absolutely huge.
“We definitely need to know how it happened, but we also need to hear from the government and from the HSE and the Department of Health, how they're going to ensure that this does not happen again,” she said.