US President Joe Biden told Russian President Vladimir Putin to take tougher action against cybercrime, in a phone call on Friday, after a slew of hacker attacks on the US and other countries.

Biden addressed the "ongoing ransomware attacks by criminals based in Russia that have impacted the United States and other countries around the world," according to the White House.

The US president "underscored the need for Russia to take action to disrupt ransomware groups operating in Russia and emphasized that he is committed to continued engagement on the broader threat posed by ransomware," the statement said.

He reiterated that the United States will take any necessary action to defend its people and its critical infrastructure in the face of this continuing challenge, according to the statement.

The two leaders spoke for roughly an hour.

Hackers have targetted hundreds of companies in ransomware attacks last weekend through a weakness in one of the products sold by US IT company Kaseya.

The group REvil demanded 70 million dollars in cryptocurrency for the decryption key to restore the companies' files, in an attack that originated in Russia, according to security researchers.

REvil was also behind previous attacks, on Colonial Pipeline, which delievers fuel along the US east coast, and on the world's largest meat processing company, JBS.

Washington has criticized two types of cyberattacks originating in Russia. The first is carried out by hackers who target countries for financial reasons, without fear of reprisals.

The other type are attacks are carried out by Russian intelligence agencies, targetting ministries, agencies and companies in the United States.

Washington has already imposed sanctions on Moscow for the latter type of attack, although the Russian government has denied responsibility. Putin has also repeatedly claimed that Russian agencies are targetted by cyberattacks.

During the two leaders' talk on Friday, Putin said despite Russia's willingness to take joint action against "criminal incidents in the information sphere," no US agencies had reached out in the course of the past month, according to Kremlin sources.

Given the severity of the challenges, the two sides should cooperate without "politicization," and government agencies should work together, according to the sources.

Both presidents have "underscored the need for factual and constructive cooperation in the field of cybersecurity," Putin said.

For his part, Biden has repeatedly called on Putin to crack down on cybercrime, most recently during their bilateral meeting in Geneva last month.

The two leaders agreed to begin talks on cybersecurity, and Biden also warned Putin there would be consequences if the attacks spread.

“Responsible countries need to take action against criminals who conduct ransomware activities on their territory,” Biden also said after the summit, in what was seen as an indirect warning.

Asked on Friday if the latest cyberattacks would have consequences, Biden said "Yes."

He said he had made it "very clear" to Putin that the United States expected him to take action.

Ransomware attacks have been on the rise for at least the past 18 months, according to White House spokesperson Jen Psaki.

Putin and Biden also discussed the UN Security Council's decision to allow cross-border humanitarian assistance to Syria during Friday's call, according to the White House.

The two also praised the joint work of their teams after the summit in Geneva. The Kremlin expressed similar sentiments.

Putin also expressed his condolences following the Surfside condo collapse in Florida.

dpa