Nuclear option? How Moscow could hit back at west for long-range strikes

Moscow has threatened to retaliate for the decision taken by the US and the UK to allow their long-range missiles to be used in strikes inside Russian territory, and warned that nothing was off the table.

- Julian Borger

So how far is Vladimir Putin prepared to go?

How likely is it that Russia would use nuclear weapons in the Ukrainian conflict?

The Kremlin has brandished its strategic arsenal over the course of the Ukrainian conflict in an attempt to deter western involvement. But the US has said it has seen no signs of unusual movement at Russian nuclear weapons storage sites, suggesting there has been no change in the physical positioning of tactical warheads.

Most experts think a Russian nuclear strike is unlikely for now but caution against complacency. Pavel Podvig, a senior researcher at the UN Institute for Disarmament Research, said he did not believe dropping a bomb in Ukraine was on Moscow's list of options, "primarily because it would not help achieve any military goals".

Furthermore, the use of a nuclear weapon in a conflict for the first time since 1945 would unite much of the world against Russia in ways Moscow could not easily predict, Podvig added.