World leaders and analysts expressed doubts that the change to Russia's nuclear doctrine amounted to much more than a new and more intense effort to deter the West.

Russia's Dmitry Medvedev warned of nuclear war if the U.S transfers nuclear weapons to Ukraine: "The consequences are obvious."

It would be "insane" for the West to give Ukraine nuclear weapons, Russia's foreign ministry has said, in response to reports suggesting such a move is possible. Listen to The World podcast while you scroll as our hosts ask: what is the endgame for Putin and Zelenskyy?

Deploying British troops to Ukraine could be like a "declaration of war against Russia" and cause a "nuclear exchange", an expert has told the Daily Express UK.

Senior Russian security official Dmitry Medvedev said on Tuesday that if the West supplied nuclear weapons to Ukraine then Moscow could consider such a transfer to be tantamount to an attack on Russia,