It appears that either the British government can't keep its lies and proof-less accusations straight or something far more nefarious is at play.

Following headlines (below) that British government scientists admitted they couldn’t tell where the poison - identified by the UK as A-234, also known as Novichok, used in the Salisbury poisoning of the Skripals - came from, undermining a number of claims to come out of Westminster, The UK Foreign Office denies claiming the nerve agent used in the Salisbury poisoning of the Skripals came directly from Russia, despite admitting it sent a tweet saying exactly that, and Boris Johnson making the same claim.

The UK Foreign Office has admitted it deleted the tweet which directly stated that the nerve agent came direct from Russia.

London has directly accused the Kremlin on at least three occasions of being behind the chemical attack on former double agent Sergei Skripal and his daughter, Yulia.

As RT notes, bizarrely, the Foreign Office denies Foreign Secretary Boris Johnson claimed the novichock “categorically” came from Russia, despite a recorded interview clearly showing he did.

The Foreign Office has not yet deleted a tweet in which the UK's ambassador to Russia, Laurie Bristow, reiterates the accusation of Moscow being behind the poisoning.

The row between Russia and Britain is reaching boiling point as officials from the OPCW meet Russian representatives on Wednesday.

As we detailed previously, following an embarrassing admission by a UK government scientist that conjured up images of Colin Powell shaking a test tube, Russia is demanding the UK apologize for rushing to judgment and blaming Russia for the attack on former double-agent Sergei Skripal and his daughter, Yulia.

During an interview with reporters in Ankara, Dmitry Peskov, a spokesman for the Kremlin, said the UK has no proof Russia was behind the poisoning and that "their theory is not confirmed in any way because it can't be confirmed." Russia has persistently denied playing any role in the poisoning.

He also suggested the UK own up to the fact that it jumped to conclusions about Russia's involvement, and admit its mistake to its EU allies.

"The British Foreign Office, which accused President Putin, the Prime Minister of Great Britain need to look their EU colleagues in the eye" over what was said

The diplomatic row caused by the poisoning has since escalated into a full-blown geopolitical crisis, with 28 countries and Nato expelling Russian diplomats, while Russia has retaliated by expelling their diplomats.

Gary Aitkenhead, the head scientist at the UK's Porton Down military laboratory facility, told Sky News that his team was unable to trace the origins of the military grade novichok nerve agent that the UK claims was used in the attack.

"We were able to identify it as novichok, to identify that it was military-grade nerve agent," Aitkenhead said. "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 chief scientist said that establishing the Novichok's origin required "other inputs," some of which are intelligence based and which only the government has access to. Aitkenhead added: "It is our job to provide the scientific evidence of what this particular nerve agent is, we identified that it is from this particular family and that it is a military grade, but it is not our job to say where it was manufactured."

Russia has demanded that the UK hand over a sample of the nerve agent for it to analyze, while the UK demanded that Russia proffer an explanation for how the nerve agent ended up outside Russia.

But after more than a month of the mainstream media refusing to conduct more than a surface level survey of the "facts", this is perhaps the best indication yet that the UK has no evidence that the Skripal poisoning - like Brexit and Trump's election - is also Russian President Vladimir Putin's fault.</s>The revelations of top British military scientists have thrown the social media into an uproar as it became apparent that new statements cast doubt on earlier claims made by Foreign Secretary Boris Johnson regarding the alleged nerve gas attack in Salisbury.Gary Aitkenhead, chief executive of the Defesce Science and Technology Laboratory at Porton Down in England, told Sky News that while the scientists managed to identify the chemical used in the Skripal poisoning case as a "military-grade nerve agent," they were unable to determine its "precise source."About two weeks earlier, however, British Foreign Secretary Boris Johnson insisted during an interview with Deutsche Welle that Porton Down scientists were "absolutely categorical: when they allegedly assured him that "there's no doubt" that the chemical came from Russia.Many social media users were nonplussed by this development, voicing their concerns via Twitter and calling on Johnson to be held accountable.</s>Click to share on WhatsApp (Opens in new window)

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THE HAGUE: The world’s chemical watchdog is to meet behind closed doors Wednesday, after a British laboratory said it had not proved that Russia manufactured a deadly nerve agent used to poison a former Russian spy.

The talks at the Organisation for the Prohibition of Chemical Weapons (OPCW) have been requested by Moscow which said it wanted to “address the situation around the allegations… in regards to the incident in Salisbury.”

“We hope to discuss the whole matter and call on Britain to provide every possible element of evidence they might have in their hands,” Russia’s ambassador to Ireland, Yury Filatov, told reporters.

On Tuesday, the British military facility analysing the nerve agent used on former Russian double agent Sergei Skripal and his daughter Yulia, said it was not in a position to say where the substance had originated.

Skripal, who has lived in Britain since a spy swap in 2010, and his daughter have been in hospital since the March 4 poisoning that London and its major Western allies have blamed on Russia.

The 41 member states of the OPCW’s executive council are to convene at 10:00 am (0800 GMT) at the organisation’s headquarters in The Hague.

The meeting comes after Moscow also received and analysed samples of the Novichok agent used in the attack.

“Russia is interested in establishing the whole truth of the matter,” Filatov said.

But Britain’s foreign ministry accused Russia of requesting the meeting to undermine the OPCW’s investigation.

“This Russian initiative is yet again another diversionary tactic, intended to undermine the work of the OPCW in reaching a conclusion,” the ministry said in a statement.

“Of course, there is no requirement in the Chemical Weapons Convention for the victim of a chemical weapons attack to engage in a joint investigation with the likely perpetrator,” it said.

Gary Aitkenhead, chief executive of the Porton Down defence laboratory, told Britain’s Sky News that analysts had identified the substance as military-grade Novichok, the word used for a category of nerve agents developed in Soviet times.

But he added: “We have not identified the precise source.”

“It is our job to provide the scientific evidence of what this particular nerve agent is, we identified that it is from this particular family and that it is a military grade, but it is not our job to say where it was manufactured,” Aitkenhead said.

“Extremely sophisticated methods” were needed to create the nerve agent, he said, adding that was “something only in the capabilities of a state actor”

Following his remarks, a British government spokesperson said Porton Down’s identification of Novichok was “only one part of the intelligence picture”.

“This includes our knowledge that within the last decade, Russia has investigated ways of delivering nerve agents probably for assassination ?- and as part of this programme has produced and stockpiled small quantities of Novichok; Russia’s record of conducting state-sponsored assassinations; and our assessment that Russia views former intelligence officers as targets,” it added.

The first use of chemical weapons in Europe since World War II has chilled Moscow’s relations with the West, as both sides have expelled scores of diplomats.

Britain has also suspended high-level diplomatic contact with Moscow.

Moscow has denied any involvement in the incident, with Russian President Vladimir Putin saying late Tuesday he hoped the OPCW meeting would put a “full stop” to the issue.

Putin added he had been informed that the British military could not prove the substance was made in Russia.

An “anti-Russian campaign” had been started with surprising speed, Putin said, reiterating Moscow’s claim that it should be allowed to take part in the investigation. – AFP</s>Moscow's foreign minister Sergei Lavrov labelled the refusal "outrageous", adding that Britain was "putting all decency aside" as the countries expel each other's diplomats.

His comments came after Russia issued a failed request to the UK to visit Ms Skripal.

On Monday, chief executive Gary Aitkenhead said the deployment was "probably only within the capability of a state actor".

Experts at Porton Down, the UK defence laboratory, are still trying to establish how the agent was administered to ex-Russian spy Sergei Skripal and his daughter Yulia on March 4.

Defence experts still do not know the "precise source" of the Salisbury spy attack - but are "completely confident" the nerve agent used was novichok.

Speaking to ITV News, Mr Aitkenhead emphasised Porton Down's belief that novichok was the agent used.

But he stressed that it was the Government's conclusion that Russia was behind the attack.

Following Mr Aitkenhead's comments, a Government spokesman said: "We have been clear from the very beginning that our world-leading experts at Porton Down identified the substance used in Salisbury as a Novichok, a military grade nerve agent.

"This is only one part of the intelligence picture. As the Prime Minister has set out in a number of statements to the Commons since March 12, this includes our knowledge that within the last decade, Russia has investigated ways of delivering nerve agents probably for assassination - and as part of this programme has produced and stockpiled small quantities of Novichoks; Russia's record of conducting state-sponsored assassinations; and our assessment that Russia views former intelligence officers as targets.

"It is our assessment that Russia was responsible for this brazen and reckless act and, as the international community agrees, there is no other plausible explanation."

Scotland Yard has said that it is their belief the pair first came into contact with novichok at their home.

"Our job within the whole of this investigation is and was to identify the nerve agent used - which is from the family of novichok," Mr Aitkenhead said.

"We provided that information to the Government who have then used a number of other sources to come to the conclusions that they have."

He added: "I can only emphasise that our job within this whole episode is to provide scientific facts, evidence and input - which was identification of the agent - and that is what we have done."</s>London (AFP) - The British military facility analysing the nerve agent used to poison a spy said on Tuesday it could not prove the substance was made in Russia, as Russian President Vladimir Putin put his hopes in a meeting with the world's chemical weapons watchdog.

Gary Aitkenhead, chief executive of the Porton Down defence laboratory, told Britain's Sky News that analysts had identified the substance as military-grade Novichok, the word used for a category of nerve agents developed in Soviet times.

But he added: "We have not identified the precise source."

"It is our job to provide the scientific evidence of what this particular nerve agent is, we identified that it is from this particular family and that it is a military grade, but it is not our job to say where it was manufactured," Aitkenhead said.

He added that "extremely sophisticated methods" were needed to create the nerve agent, and that was "something only in the capabilities of a state actor"

Following his remarks, a British government spokesman said Porton Down's identification of Novichok was "only one part of the intelligence picture".

"This includes our knowledge that within the last decade, Russia has investigated ways of delivering nerve agents probably for assassination -- and as part of this programme has produced and stockpiled small quantities of Novichok; Russia's record of conducting state-sponsored assassinations; and our assessment that Russia views former intelligence officers as targets," he added.

Former double agent Sergei Skripal, who has lived in Britain since a spy swap in 2010, and his daughter Yulia have been in hospital since March 4 after the poisoning that London and its major Western allies have blamed on Russia.

The first use of chemical weapons in Europe since World War II has chilled Moscow's relations with the West, as both sides have expelled scores of diplomats.

Britain has also suspended high-level diplomatic contact with Moscow.

Moscow has denied any involvement in the incident, with Russian Foreign Minister Sergei Lavrov on Monday suggesting that the British government may be behind the poisoning to distract attention from problems around Brexit.

Aitkenhead would not comment on whether Porton Down had developed or keeps stocks of Novichok, but he dismissed claims the agent used to poison the Skripals had come from the site.

"There is no way anything like that could have come from us or left the four walls of our facility," he said.

The Organisation for the Prohibition of Chemical Weapons (OPCW), the world's chemical watchdog, will meet Wednesday to discuss Britain's allegations that Russia was responsible for the poisoning, according to documents released on Tuesday.

The OPCW said Russia had asked for the meeting, which Putin said was aimed at putting an end to the ongoing dispute.

"We hope that during those discussions a full stop will be placed on (the issue of) what happened," he said during a visit to the Turkish capital Ankara.

The meeting request came after Moscow received and analysed samples of the Novichok agent used in the attack.

The confidential gathering will start at 10:00 am (0800 GMT) at the OPCW's headquarters in The Hague.

"We hope to discuss the whole matter and call on Britain to provide every possible element of evidence they might have in their hands," Russia's ambassador to Ireland, Yury Filatov, told reporters ahead of the OPCW meeting.

"Russia is interested in establishing the whole truth of the matter," he said.

But Britain's foreign ministry accused Russia of requesting the meeting to undermine the organisation's investigation.

"This Russian initiative is yet again another diversionary tactic, intended to undermine the work of the OPCW in reaching a conclusion," the ministry said in a statement.

"Of course, there is no requirement in the Chemical Weapons Convention for the victim of a chemical weapons attack to engage in a joint investigation with the likely perpetrator," it said.</s>Police officers stand guard outside of the home of former Russian military intelligence officer Sergei Skripal, in Salisbury, Britain, March 6, 2018. — Reuters picLONDON, April 4 — The British military facility analysing the nerve agent used to poison a spy said yesterday it could not prove the substance was made in Russia, as Russian President Vladimir Putin put his hopes in a meeting with the world’s chemical weapons watchdog.

Gary Aitkenhead, chief executive of the Porton Down defence laboratory, told Britain’s Sky News that analysts had identified the substance as military-grade Novichok, the word used for a category of nerve agents developed in Soviet times.

But he added: “We have not identified the precise source.”

“It is our job to provide the scientific evidence of what this particular nerve agent is, we identified that it is from this particular family and that it is a military grade, but it is not our job to say where it was manufactured,” Aitkenhead said.

He added that “extremely sophisticated methods” were needed to create the nerve agent, and that was “something only in the capabilities of a state actor”

Following his remarks, a British government spokesman said Porton Down’s identification of Novichok was “only one part of the intelligence picture”.

“This includes our knowledge that within the last decade, Russia has investigated ways of delivering nerve agents probably for assassination — and as part of this programme has produced and stockpiled small quantities of Novichok; Russia’s record of conducting state-sponsored assassinations; and our assessment that Russia views former intelligence officers as targets,” he added.

Former double agent Sergei Skripal, who has lived in Britain since a spy swap in 2010, and his daughter Yulia have been in hospital since March 4 after the poisoning that London and its major Western allies have blamed on Russia.

The first use of chemical weapons in Europe since World War II has chilled Moscow’s relations with the West, as both sides have expelled scores of diplomats.

Britain has also suspended high-level diplomatic contact with Moscow.

Moscow has denied any involvement in the incident, with Russian Foreign Minister Sergei Lavrov on Monday suggesting that the British government may be behind the poisoning to distract attention from problems around Brexit.

Aitkenhead would not comment on whether Porton Down had developed or keeps stocks of Novichok, but he dismissed claims the agent used to poison the Skripals had come from the site.

“There is no way anything like that could have come from us or left the four walls of our facility,” he said.

The Organisation for the Prohibition of Chemical Weapons (OPCW), the world’s chemical watchdog, will meet Wednesday to discuss Britain’s allegations that Russia was responsible for the poisoning, according to documents released yesterday.

The OPCW said Russia had asked for the meeting, which Putin said was aimed at putting an end to the ongoing dispute.

“We hope that during those discussions a full stop will be placed on (the issue of) what happened,” he said during a visit to the Turkish capital Ankara.

The meeting request came after Moscow received and analysed samples of the Novichok agent used in the attack.

The confidential gathering will start at 10:00 am (0800 GMT) at the OPCW’s headquarters in The Hague.

“We hope to discuss the whole matter and call on Britain to provide every possible element of evidence they might have in their hands,” Russia’s ambassador to Ireland, Yury Filatov, told reporters ahead of the OPCW meeting.

“Russia is interested in establishing the whole truth of the matter,” he said.

But Britain’s foreign ministry accused Russia of requesting the meeting to undermine the organisation’s investigation.

“This Russian initiative is yet again another diversionary tactic, intended to undermine the work of the OPCW in reaching a conclusion,” the ministry said in a statement.

“Of course, there is no requirement in the Chemical Weapons Convention for the victim of a chemical weapons attack to engage in a joint investigation with the likely perpetrator,” it said. — AFP</s>Boris Johnson is facing questions over a conversation he recounted with Porton Down officials about the Salisbury attack.

The Foreign Secretary was urged to explain the answer he gave when asked why he was certain the novichok nerve agent originated in Russia.

On Tuesday, Britain's military research unit revealed to Sky News it was not yet able to establish where the substance used to poison Sergei and Yulia Skripal was made.

Gary Aitkenhead, chief executive of the Defence Science and Technology Laboratory (DSTL) at Porton Down, said scientists had not "identified the precise source".

"But," he added, "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".

It came two weeks after Mr Johnson gave an interview to the German broadcaster Deutsche Welle, and was asked why he believed the chemical came from Russia.

He said: "When I look at the evidence, I mean the people from Porton Down, the laboratory..."

Mr Johnson was asked if they had samples.

He said: "They do. And they were absolutely categorical and I asked the guy myself, I said, 'Are you sure?' And he said, 'There's no doubt'."

After Mr Aitkenhead's comments to Sky News, the Foreign Office released a statement saying it had been "clear from the very beginning" that Porton Down had identified the type of substance as novichok.

"This is only one part of the intelligence picture," a spokesperson said.

They cited Prime Minister Theresa May's announcement that Russia has for the last decade "investigated ways of delivering nerve agents probably for assassination".

The spokesperson added: "It is our assessment that Russia was responsible for this brazen and reckless act and, as the international community agrees, there is no other plausible explanation."

When asked for clarification on Mr Johnson's comments about Russia being the source, a Foreign Office source told Sky News he "misspoke", but that they could "see that" interpretation.

Responding, Labour MP Chris Williamson wrote on Twitter: "Dear Britain, Boris Johnson is your Foreign Secretary and he just lied to justify our country's foreign policy. How does that make you feel?"

And shadow home secretary Diane Abbott shared another post that said: "Listen, in his own words, to Boris Johnson claim he had categorical assurances from Porton Down that the nerve agent originated from Russia. This has today been exposed as incorrect."

Previously, Mrs May had cited Porton Down research to back up the Government's stance against Russia.

She said that "positive identification of this chemical agent by world-leading experts at the Defence Science and Technology Laboratory" was one of the pieces of evidence.

She also highlighted "knowledge that Russia has previously produced this agent and would still be capable of doing so, Russia's record of conducting state-sponsored assassinations and our assessment that Russia views some defectors as legitimate targets for assassinations".</s>The Foreign Office has deleted a post on its Twitter feed stating that British scientists had established the Novichok nerve agent used in the Salisbury poisoning came from Russia.

Foreign Secretary Boris Johnson has come under fire after an announcement on Tuesday that Porton Down scientists had not verified the source of the chemical believed to have been used in the March 4 attack on Sergei and Yulia Skripal.

The tweet, issued on 22 March, said: “Analysis by world-leading experts at the Defence Science and Technology Laboratory at Porton Down made clear that this was a military-grade Novichok nerve agent produced in Russia.”

Explaining the deletion of the tweet, a Foreign Office spokesman said it had been an inaccurate summary of comments made by the UK’s ambassador to Russia, Laurie Bristow, at a briefing in Moscow.

READ MORE: Duke of Edinburgh in ‘good spirits’ after major hip operation

Referring to Dr Bristow as “HMA” - Her Majesty’s Ambassador - the spokesman said: “A full transcript and video of the briefing have been available on GOV.UK since 22 March.

“An HMA Moscow briefing on 22 March was tweeted in real time by @UKinRussia and amplified by @foreignoffice, to explain what happened in Salisbury to as wide an audience as possible. One of the tweets was truncated and did not accurately report our ambassador’s words. We have removed this tweet.”

READ MORE: Salisbury poisoning: Porton Down can’t verify nerve agent is Russian

In an interview on German TV on 20 March when he was asked why the UK believed that Russia was the source of the nerve agent, Mr Johnson said: “The people from Porton Down, the laboratory, they were absolutely categorical. I asked them that myself. I said ‘Are you sure?’. He said ‘There’s no doubt’.”

Labour leader Jeremy Corbyn said Mr Johnson either had information that he had not shared with the laboratory or it was a “bit of exaggeration” and called for a “responsible” approach to the situation.

Mr Corbyn said: “He claimed categorically - and I think he used the words 101% - that it had come from Russia. Porton Down have not said that, they said that they’ve identified it as Novichok, they cannot identify the source of it.

“Either the Foreign Secretary has information that he’s not sharing with Porton Down or it was a bit of exaggeration. I don’t know which it is, but I think we need a responsible, cool approach to this.”

Russia’s proposal for a new, joint investigation into the poisoning was voted down at the international chemical weapons watchdog at The Hague last night. Russia has accused Britain of blocking access to an investigation being carried out by the Organisation for the Prohibition of Chemical Weapons. Britain earlier said Russia’s call for an inquiry with the UK was “perverse”.

Russia lost the vote by 15 votes to six, while 17 member states abstained. China, Azerbaijan, Sudan, Algeria and Iran were among the countries that backed Russia’s motion.</s>In a major embarrassment to the UK establishment, the chief scientist from the UK's Porton Down military laboratory facility, Gary Aitkenhead, told Sky News that they had been unable to prove that the novichok nerve agent used to poison Sergei and Yulia Skripal came from Russia.

"We were able to identify it as novichok, to identify that it was military-grade nerve agent," Aitkenhead said. "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 chief scientist said that establishing the Novichok's origin required "other inputs," some of which are intelligence based and which only the government has access to.

Aitkenhead added: "It is our job to provide the scientific evidence of what this particular nerve agent is, we identified that it is from this particular family and that it is a military grade, but it is not our job to say where it was manufactured."

Oh good, at least Europe did not expel most Russian diplomats based on a Colin Powellesque assumption that since Russia is the only possible source of Novichok, so it must be. Oh wait...

Of course, this humiliation to the official narrative that Putin was clearly behind the assassination attempt all along also begs the question: whose job is it to say where the Novichok came from?

That said, it was also noted that the nerve agent involved required "extremely sophisticated methods to create, something only in the capabilities of a state actor," and that there is no known antidote to Novichok - nor was any administered to either of the Skripals.

Aitkenhead would not say whether the Porton Down facility had manufactured or maintained stocks of Novichok - long rumored to be the case.

"There is no way anything like that could have come from us or left the four walls of our facility," said the chief.

News of the UK's inability to trace the origin of the Novichok comes as a chemical weapons watchdog, the Organisation for the Prohibition of Chemical Weapons (OPCW) is set to hold an executive council meeting in The Hague on Russia's request.

Skripal and his daughter Yulia were poisoned four weeks ago in Salisbury. Russia has insisted on access to the pair.

Russia's Ambassador to the UK, Alexander Yakovenko, says that London's reluctance to share information on the March 4 poisoning of the former double agent and his daughter has led Moscow to suggest that London authorities actually perpetrated the crime.

“Our British colleagues should recall that Russia and the United Kingdom are members of the OPCW which is one of the most successful and effective disarmament and non-proliferation mechanisms," said Russian politician Vasily Shulgin. "We call upon them to abandon the language of ultimatums and threats and return to the legal framework of the chemical convention, which makes it possible to resolve this kind of situation."

“We have very serious suspicion that this provocation was done by British intelligence,” Yakovenko told Russia's NTV channel - adding however that Moscow had no direct proof, but that the UK's behavior constitutes strong circumstantial evidence in support of their theory.

Following the Skripal poisoning, the UK and several of its allies responded by expelling Russian diplomats - with the Trump administration kicking 60 Russians out of the country, and the UK expelling 23. Russia returned "fire" with the expulsion of several foreign diplomats, and a demand that Britain scale back its diplomatic mission in Russia - affecting over 50 jobs.

Yulia's condition is said to have improved significantly last week, and she is now conscious and talking. Meanwhile, Sergei Skripal reportedly remains unresponsive in critical condition.</s>British Police Community Support Officers stand on duty outside a residential property in Salisbury, southern England, on March 6, 2018. — Reuters picTHE HAGUE, April 4 — The world’s chemical watchdog is to meet behind closed doors today, after a British laboratory said it had not proved that Russia manufactured a deadly nerve agent used to poison a former Russian spy.

The talks at the Organisation for the Prohibition of Chemical Weapons (OPCW) have been requested by Moscow which said it wanted to “address the situation around the allegations... in regards to the incident in Salisbury.”

“We hope to discuss the whole matter and call on Britain to provide every possible element of evidence they might have in their hands,” Russia’s ambassador to Ireland, Yury Filatov, told reporters.

Yesterday, the British military facility analysing the nerve agent used on former Russian double agent Sergei Skripal and his daughter Yulia, said it was not in a position to say where the substance had originated.

Skripal, who has lived in Britain since a spy swap in 2010, and his daughter have been in hospital since the March 4 poisoning that London and its major Western allies have blamed on Russia.

The 41 member states of the OPCW’s executive council are to convene at 10:00 am (0800 GMT) at the organisation’s headquarters in The Hague.

The meeting comes after Moscow also received and analysed samples of the Novichok agent used in the attack.

“Russia is interested in establishing the whole truth of the matter,” Filatov said.

But Britain’s foreign ministry accused Russia of requesting the meeting to undermine the OPCW’s investigation.

“This Russian initiative is yet again another diversionary tactic, intended to undermine the work of the OPCW in reaching a conclusion,” the ministry said in a statement.

“Of course, there is no requirement in the Chemical Weapons Convention for the victim of a chemical weapons attack to engage in a joint investigation with the likely perpetrator,” it said.

Gary Aitkenhead, chief executive of the Porton Down defence laboratory, told Britain’s Sky News that analysts had identified the substance as military-grade Novichok, the word used for a category of nerve agents developed in Soviet times.

But he added: “We have not identified the precise source.”

“It is our job to provide the scientific evidence of what this particular nerve agent is, we identified that it is from this particular family and that it is a military grade, but it is not our job to say where it was manufactured,” Aitkenhead said.

“Extremely sophisticated methods” were needed to create the nerve agent, he said, adding that was “something only in the capabilities of a state actor”

Following his remarks, a British government spokesperson said Porton Down’s identification of Novichok was “only one part of the intelligence picture”.

“This includes our knowledge that within the last decade, Russia has investigated ways of delivering nerve agents probably for assassination –- and as part of this programme has produced and stockpiled small quantities of Novichok; Russia’s record of conducting state-sponsored assassinations; and our assessment that Russia views former intelligence officers as targets,” it added.

The first use of chemical weapons in Europe since World War II has chilled Moscow’s relations with the West, as both sides have expelled scores of diplomats.

Britain has also suspended high-level diplomatic contact with Moscow.

Moscow has denied any involvement in the incident, with Russian President Vladimir Putin saying late Tuesday he hoped the OPCW meeting would put a “full stop” to the issue.

Putin added he had been informed that the British military could not prove the substance was made in Russia.

An “anti-Russian campaign” had been started with surprising speed, Putin said, reiterating Moscow’s claim that it should be allowed to take part in the investigation. — AFP
Military scientists at Porton Down state they are uncertain of the source of the nerve agent used, but are "completely confident" it was a Novichok agent.