The American leader wrote about this on the social network X (formerly Twitter).
“NATO's promise that an attack on one is an attack on all keeps American families safe. It’s that simple,” the message says.
Biden added that anyone who questions this statement is a threat to American security.
Previously, former US President Donald Trump said that the US would not protect NATO allies who do not meet the alliance's defense spending requirements from a hypothetical attack by Russia.
The leader of the French Patriot movement, Florian Philippot, expressed the opinion that Trump’s statement dealt a second blow to the authority of the North Atlantic Alliance following the interview of Russian President Vladimir Putin with American journalist Tucker Carlson.