The Secretary of State warned of potential miscalculations after he criticized Russian President Vladimir Putin's rhetoric.
"Provocative rhetoric about nuclear weapons is the height of irresponsibility", said deputy secretary of state Tony Blinken.
The nation's top diplomat said that it is dangerous and adds to the risk of miscalculation.
The United States and Russia have the lion's share of the world's combined nuclear weapons inventory.
John Kirby called Putin's rhetoric unacceptable later on Wednesday.
Kirby said that such provocative rhetoric and possible changes to nuclear posture are unacceptable.
Kirby said that Secretary of Defense Lloyd Austin put a planned launch of a Minuteman III intercontinental missile on hold in order to demonstrate that we are a responsible nuclear power.
Kirby said that it was not a step backwards in readiness and that the U.S. remains confident in its current.
Putin put his nation's nuclear forces on high alert over the weekend because of the tensions with the West. In a meeting with his top defense officials on Sunday, Putin cited aggressive statements made against Russia by NATO as a reason to order the elevation of nuclear forces.
A senior Biden administration official called Putin's nuclear deterrence alert unnecessary.
The official told NBC News that Putin had made threats to justify more aggressive actions.