UP to 100 grams of liquid nerve agent were used in the attack on former Russian spy Sergei Skripal and his daughter Yulia, the head of the Organisation for the Prohibition of Chemical Weapons has said.
Ahmet Uzumcu told the New York Times the amount of Novichok used - around half a cup of liquid - suggests it was created for use as a weapon rather than for research purposes.
Mr Skripal, 66, and his 33-year-old daughter Yulia were left fighting for their lives in hospital after being found unconscious on a park bench in Salisbury on March 4.
The inquiry into the nerve agent attack in the Wiltshire city has involved 250 detectives who have gone through more than 5,000 hours of CCTV and interviewed more than 500 witnesses.
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