Russian President Vladimir Putin on Tuesday signed a revised nuclear doctrine declaring that a conventional attack on Russia by any nation that is supported by a nuclear power will be considered a joint attack on his country.

Russian President Vladimir Putin on Tuesday lowered the threshold for nuclear weapons use, just two days after the U.S. authorized Ukraine to use long-range missiles inside of Russia. Putin updated his nuclear doctrine,

President Vladimir Putin on Tuesday formally lowered the threshold for Russia’s use of its nuclear weapons, a move that follows U.S. President Joe Biden’s decision to let Ukraine strike targets inside Russian territory with American-supplied longer-range missiles.