President Joe Biden said Russia could launch a cyberattack against U.S. targets as retaliation for “the unprecedented economic costs we’ve imposed” on Russia through sanctions. Biden has urged U.S. companies to make sure their digital doors are locked because of “evolving intelligence” that Russia is considering launching cyberattacks against critical infrastructure targets as the war in Ukraine continues.

“I would respectfully suggest it’s a patriotic obligation for you to invest as much as you can” in technology to counter cyberattacks, Biden told members at the Business Roundtable’s quarterly meeting on Monday. “We’re prepared to help you, as I said, with any tools and expertise we possess, if you’re ready to do that. But it’s your decision as to the steps you’ll take and your responsibility to take them, not ours.”

The president said the federal government is “doing its part” to prepare for an attack and warned the private sector CEOs that it is also in the national interest that they do the same.

Pentagon spokesman John Kirby on Tuesday said the U.S. Department of Defense has not suffered any cyberattacks, adding that U.S. officials were open with American business leaders at Monday’s meeting about the likely risk to corporations.