British Security Minister Ben Wallace said Friday Britain believed "quite strongly" that North Korea was responsible for a global cyberattack earlier this year.

The cyberattack, which occurred in May, disrupted government services and businesses throughout the world, including one-third of English hospitals.

"North Korea was the state that we believe was involved in this worldwide attack on our systems," Wallace said in an interview with the BBC. He added the British government was "as sure as possible."

More than 300,000 computers in 150 countries were infected within days of the "WannaCry" attack, dubbed as such because the WannaCry ransomware cryptoworm was deployed.

A report released Friday by Britain's National Audit Office (NAO) said WannaCry was a relatively simple attack that Britain's National Health Service (NHS) could have prevented if it adhered to basic information technology best practices.

NHS digital security head Dan Taylor described the event as "an international attack on an unprecedented scale" and said the agency has "learned a lot."

Minister Wallace said Britain must act quickly to strengthen its cybersecurity program.

"It's a salient lesson for us all that all of us, from individuals to governments to large organizations, have a role to play in maintaining the security of our networks," Wallace said.

Ransomware attacks utilize a type of malware that encrypts files on infected computers and demands money to unlock them.