US imposes new sanctions on Russia over UK poison attack

The US will impose fresh sanctions on Russia after determining it used nerve agent against a former Russian double agent living in the UK. Sergei Skripal and his daughter Yulia were left seriously ill after being poisoned with Novichok in Salisbury in March. A UK investigation blamed Russia for the attack, but the Kremlin has strongly denied any involvement. Our correspondent in Washington DC Simon Marks talks to Guyon Espiner.