Vladimir Putin has announced the partial mobilisation of the Russian armed forces. In a pre-recorded address delayed from last night, the Russian president declared that all reservists would be called up for service in Ukraine. Nuclear war, he stressed, was not off the table.

In tones bordering on the hysterical, Putin declared that Nato leaders had been discussing the possibility and acceptability of using nuclear weapons against Russia:

‘I want to remind those who allow themselves to make such statements about Russia, we too have various means of destruction at our disposal that are more varied and modern than those owned by...