President Vladimir Putin has updated Russia’s nuclear doctrine, two days after his US counterpart Joe Biden granted Ukraine permission to strike targets deep inside Russia with US-made weapons. Under the updated doctrine issued Tuesday,

Russian President Vladimir Putin has 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.

At least 9 dead, including a child, in the second deadly Russian attack on the Sumy region in two days. As 1,000 days of war in Ukraine are marked, Vladimir Putin has approved a doctrine allowing responses with nuclear weapons to conventional attacks that pose "a critical threat to the sovereignty and territorial integrity" of Russia and Belarus.