Major Western powers are united in their conclusion. Russia, they say, carried out the first offensive use of a nerve agent in Europe since World War Two. The attack happened in the English city of Salisbury, where former spy Sergei Skripal and his daughter were poisoned with a military-grade nerve agent. This Sunday, the Russian people are expected to elect Mr Putin for a fourth consecutive term. So as Russia and the West begin a new diplomatic showdown, what does President Putin want to achieve - for himself, for Russia, and abroad?

(Photo: Russian President Vladimir Putin sunbathes during his vacation in the remote Tuva region in southern Siberia by Alexey Nikolsky/AFP/Getty Images)