North Korea is “directly involved” in the massive WannaCry malware attack earlier this year that hit more than 3,00,000 computers spread across 150 nations, resulting in damage worth billions of dollars, the US administration has said.
This is the first time that the US has blamed the country officially for the cyber-attack. Thomas Bossert, an aide to US President Donald Trump, made the accusation in the Wall Street Journal newspaper.
Bossert, who advises the president on homeland security, said the allegation was "based on evidence" and said that the United Kingdom and computer firm Microsoft also blamed affiliates of the North Korean government for the attack.
Bossert said North Korea must be held "accountable" and said the US would continue to use a "maximum pressure strategy" to hinder the regime's ability to mount cyber-attacks.
"North Korea has acted especially badly, largely unchecked, for more than a decade, and its malicious behaviour is growing more egregious. WannaCry was indiscriminately reckless," Bossert wrote.
"As we make the internet safer, we will continue to hold accountable those who harm or threaten us, whether they act alone or on behalf of criminal organizations or hostile nations," he went on.
"The tool kits of totalitarian regimes are too threatening to ignore."
The White House is expected to give an official statement blaming Pyongyang on Tuesday.
The WannaCry cyber-attack, that affected hospitals, banks and businesses around the world, hit Windows computers in May this year.
The computers affected had their contents locked, and users asked to a shell out a ransom to have their data restored.
EU police body Europol called the scale of the attack "unprecedented".