Israeli Prime Minister Benjamin Netanyahu said on Monday that the global cyber-attack encrypting files then demanding a ‘ransom’ had caused only “minor damage” to the country so far.

It emerged this week that an Israeli cyber-security firm was one of the first to spot the attack known as ‘WannaCry,’ which demands computer-users pay hundreds of pounds’ worth of online currency called Bitcoin to decrypt their files. Computer analysts describe the malicious code a self-replicating ‘worm’.

Netanyahu told his cabinet: “We’re in the midst of a global cyber-attack, but Israel has suffered only minor damages, to date. This can change at any time. That’s why we established the National Cyber Event Readiness Team a few years ago.”

He added: “We foresaw this threat and knew we needed to be prepared for the future. Obviously, there’s more work to be done to ensure we are protected against this new type of attacks.”

Israeli firm Radware advised its clients about the attack a week ago, when the first ‘phishing’ emails were detected. Since then, the malware has spread around the world, hitting public- and private-sector organisations.

In an interview with technology news site NoCamels, industry veteran Einat Meyron said: “This was a dormant worm that just waited to spread, and then infected hundreds of thousands of computers in a matter of hours.”

The malware, which spreads through a flaw in Windows software, has infected more than 200,000 computers in 150 countries, with the UK and Russia particularly hit. The identity of country of origin of the instigators is unknown, but the motive appears to be financial, not political.

However, Uri Ben Yaakov of the International Institute for Counter-Terrorism at IDC Herzliya said that while there was “no indication that terrorist organisations were behind the attack,” it is not yet known what the money raised will fund.

“Terrorist organisations also have a special desire to harm the critical infrastructure of states, as was attacked during this strike,” he said.

“The interface between terrorist organisations and organised crime, especially in the virtual world, is likely to provide terrorist organisations access to cyber-attack tools and abilities at a relatively higher level than what they currently use.”