UK unable to prove source of nerve agent used in spy attack

Britain's Porton Down defense laboratory announced on Tuesday it was unable to verify the precise source of the nerve agent used against Russian ex-spy Sergei Skripal and his daughter.

British Foreign Minister Boris Johnson told DW in March that Porton Down had "categorical" evidence that Russia was the source of the agent.

Read more: Russia says spy poisoning could be distraction from Brexit problems

Military-grade nerve agent

Gary Aitkenhead, the chief executive of the Defence Science and Technology Laboratory at the facility, told Sky News:

• "We were able to identify it as Novichok, to identify that it was military-grade nerve agent." 
• "We have not identified the precise source, but we have provided the scientific info to government who have then used a number of other sources to piece together the conclusions you have come to."
• The substance required "extremely sophisticated methods to create, something only in the capabilities of a state actor."
• "We are continuing to work to help to provide additional information that might help us get closer to [the source] but we haven't yet been able to do that."

 Russian diplomats return home amid Skripal poisoning row

Boris Johnson's claims: Johnson told DW in an exclusive interview in March that Russia was definitely behind the March 4 Salisbury attack. "They were absolutely categorical and I asked the guy myself, I said, 'Are you sure?' And he said there's no doubt. We have very little alternative but to take the action that we have taken." 

Read more: Boris Johnson: Russia's position in Skripal case is 'increasingly bizarre'

Emergency meeting: The Organization for the Prohibition of Chemical Weapons said it will hold an emergency meeting in The Hague on Wednesday at the behest of Russia.

Russian President Vladimir Putin said in Ankara that, given the inability to trace the source of the agent, "the speed at which the anti-Russian campaign has been launched causes bewilderment." He said the nerve agent could be made in some 20 nations.

Yury Filatov, Russia's ambassador to Ireland, said that if the UK was unable to provide evidence of Russia's involvement then "there are ample grounds to assume that [they] are dealing with a grand scale provocation organized in London aimed to discredit Russia."

Russian retribution: Scores of Russian diplomats and spies were expelled from a series of British allies following the attack on the basis that Russia was behind the attack.

aw/jm (AP, AFP, Reuters)

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