WASHINGTON — President Joe Biden said Wednesday he would “deliver” a message to Russian President Vladimir Putin about the latest ransomware attacks targeting American businesses, setting up a test of Biden's ability to balance his pledge to respond firmly to cyber breaches with his goal of developing a stable relationship with Russia.

The administration faces few easy options for a ransomware threat that in recent months has emerged as a major national security challenge, with attacks from Russia-based gangs that have targeted vital infrastructure and extorted multimillion-dollar payments from victims.

The White House says the latest attack affected as many as 1,500 businesses worldwide. The malicious intrusion exploited a powerful remote-management tool run by Miami-based software company Kaseya. It occurred weeks after Biden made clear to Putin that the U.S. would not tolerate attacks.