Inspectors from the Organization for the Prohibition of Chemical Weapons (OPCW) are seeking to exhume the bodies of victims from the suspected chemical weapons attack in Douma, Syria, on the theory that traces of nerve agents like sarin gas will linger in human tissue for much longer than environmental samples from the attack site. He told the New York Times: “That quantity – a range from slightly less than a quarter-cup to a half-cup of liquid – is significantly larger than the amount that would be created in a laboratory for research purposes, meaning that it was almost certainly created for use as a weapon.”

Within hours of the report, however, startled chemical weapons experts were challenging the figure, insisting a miscommunication had occurred. The poisoning left Mr Skripal, 66, and his 33-year-old daughter Yulia fighting for their lives after being found slumped on a bench at The Maltings shopping centre in Salisbury on 4 March. 'Deny, distract and blame': how Russia fights propaganda war Read more

He said: “For research activities or protection you would need, for instance, five to 10 grams or so, but even in Salisbury it looks like they may have used more than that, without knowing the exact quantity, I am told it may be 50, 100 grams or so, which goes beyond research activities for protection.”

Samples of the agent were collected from the door handle of the Skripal home, the park bench where the two collapsed and “a few other places where the Skripals were present,” he added. Russia’s military intervention in Syria remains ongoing. We understand it was also of high purity.”

Last month, the Department for Environment, Food and Rural Affairs confirmed the nerve agent used in the attack was delivered in liquid form.
The head of the Organization for the Prohibition of Chemical Weapons, Ahmet Uzumcu says that up to 100 grams of liquid nerve agent were used in the chemical attack on Sergei and Yulia Skripal – around half a cup of liquid, suggesting it was intended for use as a weapon and was not created for research purposes.