US Warns of ‘Catastrophic Consequences’ If Russia Uses Nukes

Jake Sullivan says the US would respond 'decisively'

National Security Advisor Jake Sullivan on Sunday threatened that the US would respond if Russia used nuclear weapons in Ukraine and said Moscow would face “catastrophic consequences.”

“If Russia crosses this line, there will be catastrophic consequences for Russia. The United States will respond decisively,” Sullivan said on NBC’s Meet the Press.

Sullivan didn’t detail exactly what the US response would be, although his wording suggests that the US could carry out a nuclear strike on Russia, which could lead to a nuclear exchange that could kill billions of people. But there’s still no sign that Russia is preparing to use a nuclear weapon in Ukraine, something US officials acknowledged in comments to The New York Times.

Sullivan said that the US has “spelled out in greater detail exactly what that would mean” in private messages to Moscow. The Washington Post reported that the US has been warning Russia over the past few months through backchannels of grave consequences if Moscow uses nuclear weapons. But the report said the warnings were intentionally vague.

Sullivan said that the Biden administration has been in frequent contact with Russia, although there have been no recent public high-level meetings.

Sullivan’s comments came after Russian President Vladimir Putin warned Russia could use nuclear weapons to protect its “territorial integrity.” Other Russian officials have made clear that the warning applies to territory Moscow will likely absorb after the referendums on joining Russia being held in Russian-controlled areas of Ukraine.

Despite the soaring tensions and talk of nuclear weapons, the Biden administration has shown no sign of backing down on its support for Ukraine.

Author: Dave DeCamp

Dave DeCamp is the news editor of, follow him on Twitter @decampdave.