Ukraine ex-leader Poroshenko sees 'Russian fifth column' in power

Ukraine's ex-president Petro Poroshenko has told the BBC that Russia is influencing President Volodymyr Zelensky.

Mr Poroshenko is being prosecuted for alleged abuse of office - something he dismisses as political "revenge".

He said people close to Mr Zelensky were working in Russia's interests, as a "fifth column".