London: A “high purity” dose of the toxic nerve agent Novichok was used to poison ex-spy Sergei Skripal, the international chemical weapons watchdog has confirmed.

The chemical severely injured him, his daughter Yulia and a policeman who tried to help them, the Organisation for the Prohibition of Chemical Weapons said in its report submitted to the UK and shared with all parties to the Chemical Weapons Convention – including Russia.

The OPCW took samples at the scene in Salisbury and blood from the victims and analysed them at four separate independent laboratories.

The results “confirm the findings of the United Kingdom relating to the identity of the toxic chemical that was used in Salisbury and severely injured three people,” the OPCW said in a public summary of its secret report.