LONDON -- The United States and Britain blamed the Russian government on Thursday for a cyberattack that hit businesses across Europe last year. The U.K. accused Moscow of "weaponizing information" in a new kind of warfare, and the White House said "the Russian military launched the most destructive and costly cyber-attack in history."

"The attack, dubbed 'NotPetya,' quickly spread worldwide, causing billions of dollars in damage across Europe, Asia, and the Americas," said a statement from the White House press secretary. "It was part of the Kremlin's ongoing effort to destabilize Ukraine and demonstrates ever more clearly Russia's involvement in the ongoing conflict. This was also a reckless and indiscriminate cyber-attack that will be met with international consequences."

Earlier, British Foreign Minister Tariq Ahmad said "the U.K. government judges that the Russian government, specifically the Russian military, was responsible for the destructive NotPetya cyberattack of June 2017."

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The fast-spreading outbreak of data-scrambling software centered on Ukraine -- embroiled in a conflict with Moscow-backed separatists in the country's east. It spread to companies that do business with Ukraine, including U.S. pharmaceutical company Merck, Danish shipping firm A.P. Moller-Maersk and FedEx subsidiary TNT. Ahmad said the "reckless" attack cost organizations hundreds of millions of dollars.

British Defense Secretary Gavin Williamson accused Russia of "undermining democracy, wrecking livelihoods by targeting critical infrastructure, and weaponizing information" with malicious cyberattacks.

"We must be primed and ready to tackle these stark and intensifying threats," Williamson said.

Danish defense minister Claus Hjort Frederiksen said intelligence agencies in Britain, Denmark and elsewhere had uncovered the Russian responsibility.

Speaking at a NATO defense ministers' meeting in Brussels, he said the hack was meant to cause damage and should "be compared with a military attack."

President Vladimir Putin's spokesman, Dmitry Peskov, denied Russia's involvement.

"We categorically deny the accusations. We consider them unfounded and baseless and see them as continuation of groundless Russophobic campaign," he said in a conference call with reporters.