The attack launched in June 2017 by the Russian military “spread worldwide, causing billions of dollars in damage across Europe, Asia and the Americas,” White House Press Secretary Sarah Sanders said in a statement. President Vladimir Putin’s spokesman said the Kremlin categorically denies involvement and called the claims “unsubstantiated and groundless.”

“This is nothing but a continuation of a Russophobic campaign that is not based on any evidence,” Kremlin spokesman Dmitry Peskov said earlier Thursday. The cyberattack was “reckless and indiscriminate,” she added, and “will be met with international consequences.”

Britain announced earlier Thursday that Russia was “almost certainly” responsible for the NotPetya attack, citing findings reached by the U.K.’s National Cyber Security Centre.
The United Kingdom government and the United States White House accuse the Russian military of being responsible for the launch of the NotPetya malware in June 2017. The White House calls it the most destructive and costly cyberattack in history and says Russia will be met with unspecified "international consequences". Russia denies responsibility and dismisses the accusation as "groundless", lacking evidence, and "Russophobic".