President Joe Biden said on Monday that intelligence indicated a growing Russian cyber threat to the US.
He said Russia was "exploring" cyber attack, but the US would use "every tool" to prevent and respond to such a move.
Mr Biden suggested Moscow could act in retaliation for sanctions imposed on it after Russia's invasion of Ukraine.
Russia's foreign ministry has said bilateral ties between Moscow and the US were on the "verge of rupture".
Mr Biden has previously warned of a possible cyber attack from Russia, saying on 24 February the US was prepared to respond.
In Monday's statement, Mr Biden said that intelligence had been "evolving", and that the US believes the "Russian government is exploring options".
Mr Biden also called for US companies to "accelerate efforts to lock their digital doors".
"You have the power, the capacity, and the responsibility to strengthen the cybersecurity and resilience of the critical services and technologies on which Americans rely. We need everyone to do their part," he said.
Mr Biden said the potential "malicious cyber activity" could be prompted by the "unprecedented economic costs" caused by economic sanctions imposed by the West.
