Western leaders are preparing for Vladimir Putin to use “whatever tools he’s got left” including nuclear threats and cyber-attacks in response to an expected Ukrainian counter-offensive against Russia. British officials at the G7 foreign ministers’ summit in Japan said they were expecting Russia to retaliate and “must be prepared” for extreme tactics as it attempted to hold on to Ukrainian territory. The former Russian president Dmitry Medvedev said last month that Moscow was ready for the Ukrainians to hit back, warning that his country would use “absolutely any weapon” if Kyiv attempted to retake Crimea, which was annexed by Russia...