Earlier on Friday, the national security adviser to Britain's prime minister told NATO Secretary General Jens Stoltenberg in a letter that email accounts of Yulia had been targeted in 2013 by cyber specialists from Russia's GRU military intelligence service.
Investigators from the watchdog said the nerve agent was "of high purity".
It is noted that the word "Novichok" was introduced by the West in the mid-1990s in order to identify a number of chemicals developed there based on information provided by Russian immigrant researchers.
It goes on to say that "during the 2000s", Russian Federation created a special unit to develop chemical weapons for use as tools in state-sponsored attacks and to "train personnel from special units in the use of these weapons".
"This programme subsequently included investigation of ways of delivering nerve agents, including by application to door handles", the letter says.
Britain says that Yulia Skripal's email was under attacked from the GRU in 2013..
Besides, the poisoning of Alexander Litvinenko in 2006 was mentioned in the letter as well.
Nevertheless, the attack has prompted the biggest Western expulsion of Russian diplomats since the Cold War, with the UK's allies in Europe and North America concurring that Moscow was either responsible for the attack or had lost control of the nerve agent.
Sergei Skripal remains in hospital in serious condition, while Yulia Skripal has been released.
Double Russian agent Sergei Skripal has been found unconscious after being exposed to an unknown substance.
This is an image of the daughter of former Russian Spy Sergei Skripal, Yulia Skripal taken from Yulia Skipal's Facebook account on Tuesday March 6, 2018.
Britain has asked for a meeting of OPCW 's executive council on Wednesday to discuss the organisation's findings, and Britain is also seeking a meeting of the U.N. Security Council next week on the chemical weapons report.
According to Sedwill, Russia regards some of its defectors as "legitimate targets for assassination".
Sedwill said that after the Soviet Union collapsed, Russian Federation signed the Chemical Weapons Convention without reporting its ongoing work on Novichoks.
Russian Federation strongly denies the UK's claims about Novichok, saying it destroyed its entire Soviet-era chemical weapons arsenal a year ago under global oversight.
Dossier alleges Kremlin has been "producing and stockpiling small quantities of novichok" for years.
Moscow has hit back by expelling Western diplomats, questioning how Britain knows that Russian Federation was responsible and suggesting it stemmed from a plot by British secret services.
"The results of analysis by OPCW-designated laboratories. confirm the findings of the United Kingdom relating to the identity of the toxic chemical", the published summary said.
"We are not allowed to see our citizens, talk to doctors, have no idea about the treatment the Russian nationals receive", he said.
On Wednesday she said she did not now wish to take up an offer of consular assistance from the Russian embassy, according to a note released by London's Metropolitan Police.