President Vladimir Putin has approved Russia's updated nuclear doctrine to share the country's nuclear deterrence with its allies—mirroring NATO 's "attack on one member is an attack on all" doctrine, as President Zelensky of Ukraine marks 1,000 days since Russia invaded his country.

Ukrainian troops launched an attack against a Russian border region with six US- long-range missiles, Moscow says. It comes after Vladimir Putin approved an updated doctrine lowering the threshold for the use of nuclear weapons.

President Biden will allow Ukraine to carry out long-range strikes on Russian targets, according to reports. How could it impact the war?