President Joe Biden appeared to reassure Americans who may be concerned about nuclear war.

As Biden was leaving a Black History Month event at the White House, he was asked whether Americans should be worried about a nuclear war breaking out.

Biden provided a one-word answer: "No."

Less than a week into the invasion of Ukraine, Russian President Vladimir Putin ordered the country's nuclear forces to be put on high alert. The move came as the international community continued to pile on sanctions and isolate Russia for the invasion.

Daryl Kimball, executive director of the Arms Control Association, told The Associated Press that he was not surprised by Putin's decision.

“Inserting nuclear weapons into the Ukraine war equation at this point is extremely dangerous, and the United States, President Biden, and NATO must act with extreme restraint," Kimball said.

The U.S. and Russia have the largest nuclear arsenal in the world. However, Russia has reportedly never used a nuclear weapon during war.