Vladimir Putin has blamed the US for the global cyber attack that has crippled computer systems around the world since Friday.
Mr Putin said Russia had "nothing to do" with the attack and blamed the US for creating the hacking software that affects Microsoft computers.
"Malware created by intelligence agencies can backfire on its creators," said the Russian president, speaking to media in Beijing.
He added that global leaders needed to discuss cyber security at a "serious political level" and said the US has backed away from signing a cyber security agreement with Russia.
Authorities fear a second wave of the "WannaCry" ransomware could hit systems.
It has now emerged that criminal hacking groups have repurposed a second classified cyber weapon stolen from US spies and have made it available on the so-called dark web after the success of the WannaCry attack.
The 'Financial Times' reported that the hacking tool, developed by the US National Security Agency and codenamed 'EsteemAudit', has been adapted and is now available for criminal use, according to security analysts.
Latest evidence suggests "phishing" emails are unlikely to have caused the global cyber attack that wreaked havoc at dozens of British NHS hospitals and hit more than 200,000 computers in 150 countries.
Security experts have disputed claims the virus was spread through suspicious emails, saying computers were vulnerable to the bug regardless of how vigilant users were.
Experts said that unless IT departments patched the virus and backed up their files they could be hit by the attacks.
Affected UK hospitals were criticised for not adding the patch despite warnings from NHS Digital a month ago that they were vulnerable to a possible attack.
NHS systems appeared to be largely up and running yesterday, although seven out of the 47 hospital trusts hit by last week's attack are still seeking emergency support, according to NHS Digital.
Japanese computer experts said around 2,000 PCs had been affected while the Chinese news agency Xinhua reported that almost 30,000 had been hit.