Spy poisoning: Boris Johnson criticises Russia's response
Foreign Secretary Boris Johnson has criticised Russia's response to the poisoning of an ex-spy in the UK, describing it as "smug sarcasm".
Sergei Skripal and his daughter Yulia remain critically ill in hospital after being exposed to what the UK government says is a military-grade nerve agent in Salisbury.
Speaking on the BBC's Andrew Marr Show, Mr Johnson said Russia had every opportunity to explain how the poisoning may have occurred.