By Chris Kitching
Russia claims the substance used to poison double agent Sergei Skripal and his daughter Yulia was an agent called BZ that has been used by Nato states including the UK and US.
It was the Kremlin’s latest denial that the pair were targeted with a Novichok nerve agent developed by the Soviet military and latest attempt to discredit the findings of independent chemical weapons experts.
Scientists from the Nobel Prize-winning OPCW found that “high purity” Novichok was used in the poisoning, backing the UK.
Russia’s Foreign Minister Sergey Lavrov claims a Swiss lab found that a BZ agent was used against the Skripals.
He said the toxin was never produced in Russia, but was “in service” in the UK, US and other Nato states, state media reported.
Russia has denied that it was involved in the poisoning and that a Soviet military-grade nerve agent was used in the attempted murder of the Skripals.
It has repeatedly used state media to accuse the UK of responsibility and deny Kremlin involvement.
The father and daughter were critically ill when they were found slumped on a bench in Salisbury city centre in Wiltshire on March 4.
Ms Skripal, 33, has been released from hospital while Mr Skripal, 66, remains in hospital, but is no longer in a critical condition.
Mr Lavrov claims the Skripals were poisoned with a toxin known as 3-Quinuclidinyl benzilate or BZ, rejecting the findings of chemical weapons experts.
The Organisation for the Prohibition of Chemical Weapons (OPCW) found that “high purity” Novichok was used in the attempted murder.
It said the nerve agent was detected in environmental samples collected in Salisbury and in blood samples taken from the Skripals and Det Sgt Nick Bailey, a Wiltshire Police officer who fell seriously ill while working on the case.
Foreign Secretary Boris Johnson said the findings backed the UK’s position that Russia carried out the attack on UK soil.
He said: “There can be no doubt what was used and there remains no alternative explanation about who was responsible – only Russia has the means, motive and record.”
The largest concentration of the nerve agent has been found at the front door of Mr Skripal’s home in Salisbury, the UK has said.
Russia has challenged claims that it was involved, telling the UK to provide proof. It has also sought access to Ms Skripal, who was reportedly in a secure location after being discharged from hospital.
Mr Skripal was a Russian military intelligence colonel who was jailed in Russia in 2006 after he became a double agent and provided secrets to the West.
Mr Skripal was pardoned in 2010 and released as part of a Cold War-style spy swap. He was granted refuge in the UK, where he settled in Salisbury.
It was claimed this week that Russia had been spying on Mr Skripal and his daughter for at least five years.