Europol's Wainwright said few banks in Europe had been affected, having learned through the "painful experience of being the number one target of cyber crime" the value of having the latest cyber security in place.
At the height of the attack Friday and early Saturday, 48 organizations in the NHS were affected, and hospitals in London, North West England and Central England urged people with non-emergency conditions to stay away as technicians tried to stop the spread of the malicious software.
Initial reports said just one Australian business had been impacted, but Cyber Security Minister Dan Tehan confirmed two others were also hit in an interview with the ABC this morning. Government agencies and universities were among those hit as well as petrol stations, ATMs and hospitals, it said. "The numbers are going up", he added.
Scores of organisations inside the NHS, which provides free medical care for all and is a source of pride for Britons, were hit by the ransomware on Friday.
Some hospitals still asked patients on Monday to seek treatment only for life-threatening emergencies.
In an interview with the BBC's Andrew Marr Show, Fallon said the British Government under Prime Minister Theresa May had identified in its security review that cyber threats were one of the top three greatest threats for the country.
Wallace denied that underinvestment in the NHS - a key claim of the opposition Labour Party ahead of the June 8 election - may have left health services exposed to such attacks.
"The government's response has been chaotic, to be frank,"Labour's health spokesman Jon Ashworth said". "They've complacently dismissed warnings which experts, we now understand, have made in recent weeks".
Britain plans to spend about 120 billion pounds ($155 billion) on the Department of Health in 2017, according to the King's Fund think tank.
The NHS, which was showcased in the opening ceremony of the 2012 Olympic Games, employs more than 1.5 million people, making it the world's fifth biggest employer after the United States and Chinese militaries, Walmart and McDonald's.
Wainwright said the attack was indiscriminate, fast-spreading and unique, because the ransomware was being used in combination with a worm, which means the infection of one computer automatically could spread it through a whole network. However, there is no guarantee and you will get access back to your data after you make the payment.
Britain's spending watchdog, the National Audit Office, warned in 2014 that some NHS organisations had "limited understanding of the threat and they do not yet understand what would represent an appropriate level of threat protection".
Asked if warnings had been ignored, Mrs May said: "No".
Lancashire Teaching Hospitals NHS Foundation Trust, which runs Chorley and Preston hospitals, said the "majority of planned procedures and operations scheduled for Monday have been postponed".
The UK government called a meeting of its crisis response committee, known as Cobra, to discuss how to handle the situation. A spokesman for May said the annual information technology budget in the NHS was 4.2 billion pounds and that an extra 50 million pounds had been allocated for updating cyber security.