At least 30 health service organisations in England and Scotland have been affected by thehack attack, while others shut down servers as a precautionary measure to avoid contagion.
Russia's Interior Ministry released a statement acknowledging a ransomware attack on its computers, adding that less than 1% of computers were affected, and that the virus is now "localized".
A spokesman for Barts Health NHS Trust in London said it was experiencing "major IT disruption" and delays at all four of its hospitals.
A large cyberattack crippled computer systems at hospitals across England on Friday, with appointments canceled, phone lines down and patients turned away.
The British prime minister, Theresa May, and NHS Digital said they were not aware of any evidence patient records had been compromised in Friday's attack, which is thought to have affected computers in almost 100 countries.
NHS England said patients needing emergency treatment on Saturday should go to A&E or access emergency services as they normally would.
A British medical student found widespread computer issues when visiting two London hospitals.
The state-run NHS declared a "major incident" after the cyber attacks, which prompted some hospitals to divert ambulances and scrap operations.
"We are also working with CERT NZ to provide information on how individuals, small businesses and operators of larger systems can reduce their vulnerability to ransomware attacks", he said.
The Government Communications Security Bureau says it has not received any reports of the "WannaCry" malware infection affecting computers in New Zealand. In February 2016 a Los Angeles hospital, the Hollywood Presbyterian Medical Center, paid $17,000 in bitcoins to hackers who took control of its computers for more than a week.
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Emmanuelle Ménard, l'épouse du maire de Béziers, est candidate aux législatives dans la 6e circonscription de l'Hérault. En même temps que sa femme, Robert Ménard a confirmé mercredi soir sa candidature sur son propre compte twitter.
Telefonica said the attack was limited to some computers on an internal network and had not affected clients or services.
"We're not aware of any evidence that patient data has been compromised".
British Prime Minister Theresa May says a cyberattack initially believed to be targeting only hospitals in the United Kingdom has now gone beyond, involving potentially dozens of countries.
"Russia, Ukraine and Taiwan leading", Avast researcher Jakub Kroustek tweeted on Friday.
"When dealing with ransomware, advance security protections, basic cyber hygiene, tested disaster recovery plans and employee training are critical to protecting data".
He said many NHS hospitals in Britain use Windows XP software, introduced in 2001, and as government funding for the health service has been squeezed, "IT budgets are often one of the first ones to be reduced".
The Royal London, St Bartholomew's, Whipps Cross and Newham are some of numerous hospitals to be hit by the attack, with messages flashing up saying that their files have been encrypted and they must pay cash or lose access to them.
The ransomware, called "WannaCry", is spread by taking advantage of a Windows vulnerability that Microsoft released a security patch for in March.
Authorities in Britain have been braced for cyber attacks in the run-up to the vote, as happened during last year's US election and on the eve of the French vote.
However, shadow health secretary Jonathan Ashworth said the attack was "terrible news and a real worry for patients" and urged the Government to be "clear about what's happened". "I did not expect an attack on this scale".
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