Introduction

Putin’s main rival, opposition politician Alexei Navalny, is dead according to the Russian prison service.

This is today's Ukrainecast episode, and we thought you might want to listen to it.

BBC correspondent Sarah Rainsford, who was herself expelled from Russia, explains what we know so far - and if the Kremlin could face any consequences. And Georgian-Russian writer Boris Akunin, a long-standing critic of Putin and personal friend of Navalny, gives his reaction to the news.