If the OPCW fails to inspect the Porton Down chemical weapons centre near Salisbury, this will mean the organisation is biased, because the purported amounts of Novichok could only have been manufactured in situ, i.e. in immediate proximity to the dispersal site.
Many competing and contradictory stories promulgated by Russian state-controlled media, the only connecting thread being to confuse their audience and exclude any possibility of Russian involvement. euvsdisinfo.eu/disinformation-cases/?text=sergei+skripal&disinfo_issue=&date= and euvsdisinfo.eu/report/porton-down-might-be-responsible-for-the-chemical-attack-in-the-uk/,
On September 5, UK counter-terrorism police released images of two suspects in connection with the Salisbury attack. news.met.police.uk/news/counter-terrorism-police-release-images-of-two-suspects-in-connection-with-salisbury-attack-320534, , www.bbc.com/news/uk-45421445,
On September 6, France, Germany, US and Canada stated that they have full confidence in the British assessment that the two suspects were officers from the Russian military intelligence service, also known as the GRU, and that this operation was almost certainly approved at a senior government level. www.gov.uk/government/news/salisbury-attack-joint-statement-by-leaders-of-france-germany-the-united-states-canada-and-the-united-kingdom,
The toxin was identified as a nerve agent at Porton Down, which is Britain's military research base. They have not done tests with nerve agents since 1989, but are still able to identify these toxins, in order to protect British civilians and troops from attacks www.bbc.com/news/av/uk-43335148/porton-down-britain-s-secret-research-facility
The nerve agent has been identified as Novichok (which means newcomer in Russian). It is known to be more powerful than VX and was developed in Russia in the 1970s and 1980s www.voanews.com/a/british-prime-minister-russia-poisoning-spy/4294683.html. It's so unusual, that very few scientists outside of Russia have any real experience in dealing with it and no country outside of Russia is known to have developed the substance edition.cnn.com/2018/03/13/europe/what-is-novichok-nerve-agent-intl/index.html, theconversation.com/what-we-know-about-novichok-the-newby-nerve-agents-linked-to-russia-93264
In its statement, the European Union expressed shock at the offensive use of any military-grade nerve agent, of a type developed by Russia, for the first time on European soil in over 70 years. www.consilium.europa.eu/en/press/press-releases/2018/03/19/statement-by-the-foreign-affairs-council-on-the-salisbury-attack/