MOSCOW (Reuters) -President Vladimir Putin said on Thursday that the Ukraine war was escalating towards a global conflict after the United States and Britain allowed Ukraine to hit Russia with their weapons, and warned the West that Moscow could strike back.

Putin is the primary decision-maker on the use of Russia's nuclear arsenal. The doctrine said any attack by a non-nuclear power supported by a nuclear power would be considered a joint attack, and that any attack by one member of a military bloc would be considered an attack by the entire alliance, it said.

Russian President Vladimir Putin said his forces may use a new missile again after targeting Ukraine in retaliation for Kyiv’s use of American and British-made weapons on Russian territory this week.