Russia has documents indicating that Novichok gas was being developed in the United States, said Igor Rybalchenko, head of the laboratory for chemical and analytical control at the Russian Ministry of Defense, during a broadcast on the Russia-1 television channel, RIA Novosti has reports.
According to Rybalchenko, Russian specialists found informational records regarding an organophosphorus substance with a "strong lethal effect" dating back to 1998 in the Spectral Library of the US National Standards Bureau.
"Now it has turned out that, judging by the name of that agent, it was Novichok A234," Rybalchenko said.
He noted that members of the US Army Chemical Research and Development Center established the connection to the database.
According to Rybalchenko, formulas published in a book by chemist Vil Mirzayanov, who emigrated to the US, would allow such a compound to be synthesized "in any prepared laboratory."
Former GRU (Russia’s Main Intelligence Directorate) intelligence officer Sergei Skripal and his daughter Yulia were previously found poisoned and unconscious in the center of the town of Salisbury on March 4.
The act has been classified as an ‘attempted murder’ during the investigation, although it is possible the incident could be re-classified as a terrorist attack, taking into account the potential danger of the applied nerve agent used in the attack.
According to British experts, the Novichok agent used to poison Skripal and his daughter was developed and manufactured in the Russian city of Shikhany (in Saratov Oblast), where Russia has established its primary military research facility.
The Russian Federation claims that Novichok can be obtained in any former USSR country, particularly in Georgia and Ukraine; the Russian Ministry of Foreign Affairs has also stated that there had never been research into the development of chemicals codenamed Novichok in Russia nor the Soviet Union.
British Prime Minister Theresa May announced that there is a "high probability" that Russia is guilty of the attempted murder of former Russian spy and GRU officer Sergei Skripal and his daughter Yulia.
The countries of the European Union also consider it highly probable that responsibility for the poisoning of former double agent Sergei Skripal lies with Russia.
The UK has expelled 23 Russian diplomats from the country. Russia responded by saying that such a decision is "a hostile step, totally unacceptable, unjustified and short-sighted."