Russia-US tensions: Cabinet gives May the go-ahead for Syria strike 'to deter further use of chemical weapons by the Assad regime'

The nerve agent used to poison former Russian double agent Sergei Skripal and his daughter was "of high purity," the international chemical weapons watchdog has said.

Responding to the report's findings, Boris Johnson, the foreign secretary, said "only Russia has the means, motive and record" to launch the attack.

Mr Johnson said "there can be no doubt what was used and there remains no alternative explanation about who was responsible - only Russia has the means the motive and record." 

The nerve agent poisoning of Sergei Skripal in Salisbury shows "how reckless Russia is prepared to be," the head of GCHQ has said.

In his first public speech since taking over as head of Britain's spy agency, Jeremy Fleming said the attack on the former Russian double agent demonstrated Russia's "unacceptable" behaviour. 

"You've heard it said, and I'll repeat, the attack on Sergei and Yulia Skripal in Salisbury, was the first time a nerve agent had been deployed in Europe since the Second World War," Mr Fleming told a cyber conference in Manchester.

"That's sobering. It demonstrates how reckless Russia is prepared to be, how little the Kremlin cares for the international rules-based order."

Jeremy Corbyn declined to say whether Vladimir Putin bears any responsibility for the nerve agent attack in Salisbury.

The Labour leader was asked whether he thought the Russian president was responsible for the poisoning of Sergei Skripal and his daughter Yulia on a visit to a school in Derby.

Mr Corbyn said: "I think somebody was obviously responsible for it and that somebody has to be found. My view is that the use of nerve agents is obviously vile and wrong. And the chemical weapons convention inspection must take place and those that did it must be held responsible.

"Clearly, novichok is of Russian design and Russian origin, but the investigation should take place on this."

The student asked: "You don't think it's Putin?"

Mr Corbyn replied: "I don't say it is or isn't. I say an investigation must take place so the finger of blame can be pointed with evidence behind it. I think any differences between countries have got to be evidence-based so that we do have a legal basis for our complaints against whoever did it.

"I'm pleased that both the Skripals seem to be recovering although I think the long-term effects of novichok will not go away just because they've recovered from the immediate effects of it."

Vladimir Putin has warned Israel's prime minister, Benjamin Netanyahu, Syria's neighbouring countries must "show restraint", after claims Israel was behind a recent air strike on a Syrian air base.

"President Putin spoke on the phone with Netanyahu on the latter's initiative, stressing the need for Syria's neighbours to show restraint, avoiding actions that could destabilize this war-torn country and respect its sovereignty and integrity," Alexander Yakovenko, Russian ambassador to the UK, tweeted.

Germany will not join any strikes on Syria, Angela Merkel has said.

The German chancellor said a whole range of measures must be considered. 

"Germany will not take part in possible - there have not been any decisions yet, I want to stress that - military action," she said.

"But we support everything that is being done to show that the use of chemical weapons is not acceptable," she added.

The Syrian government is now in full control of Douma, the site of a suspected chemical weapons attack over the weekend, the Russian military has announced.

Douma was the last rebel bastion in eastern Ghouta, the biggest rebel stronghold near Damascus.

On Sunday, rebel-group Jaish al-Islam agreed to withdraw hours after a suspected chemical weapons attack.

Both the Syrian regime and Russia have called reports of the attack bogus. 

"The raised state flag over a building in the town of Douma has heralded the control over this location and therefore over the whole of eastern Ghouta," Major-General Yuri Yevtushenko, head of the Russian Peace and Reconciliation Centre in Syria, was quoted as saying by Russian news agencies.

Russian military police were deployed in Douma in accordance with the rebel surrender deal, Russia's RIA news agency reported.

Here is the summary of the OPCW report on the poisoning of Sergei Skripal in Salisbury:

1. The United Kingdom of Great Britain and Northern Ireland requested technical assistance from the OPCW Technical Secretariat under subparagraph 38(e) of Article VIII of the Chemical Weapons Convention in relation to an incident in Salisbury on 4 March 2018 involving a toxic chemical-allegedly a nerve agent-and the poisoning and hospitalisation of three individuals. The Director-General decided to dispatch a team to the United Kingdom for a technical assistance visit (TAV).

2. The TAV team deployed to the United Kingdom on 19 March for a pre-deployment and from 21 March to 23 March for a full deployment.

3. The team received information on the medical conditions of the affected individuals, Mr Sergej Skripal, Ms Yulia Skripal, and Mr Nicholas Bailey. This included information on their acetylcholinesterase status since hospitalisation, as well as information on the treatment regime.

4. The team was able to collect blood samples from the three affected individuals under full chain of custody for delivery to the OPCW Laboratory and subsequent analysis by OPCW designated laboratories, and conducted identification of the three individuals against official photo-ID documents.

5. The team was able to conduct on-site sampling of environmental samples under full chain of custody at sites identified as possible hot-spots of residual contamination. Samples were returned to the OPCW Laboratory for subsequent analysis by OPCW designated laboratories.

6. The team requested and received splits of samples taken by British authorities for delivery to the OPCW Laboratory in Rijswijk, the Netherlands, and subsequent analysis by OPCW designated laboratories. This was done for comparative purposes and to verify the analysis of the United Kingdom.

7. The team was briefed on the identity of the toxic chemical identified by the United Kingdom and was able to review analytical results and data from chemical analysis of biomedical samples collected by the British authorities from the affected individuals, as well as from environmental samples collected on site.

8. The results of analysis of biomedical samples conducted by OPCW designated laboratories demonstrate the exposure of the three hospitalised individuals to this toxic chemical.

9. The results of analysis of the environmental samples conducted by OPCW designated laboratories demonstrate the presence of this toxic chemical in the samples.

10. The results of analysis by the OPCW designated laboratories of environmental and biomedical samples collected by the OPCW team confirm the findings of the United Kingdom relating to the identity of the toxic chemical that was used in Salisbury and severely injured three people.

11. The TAV team notes that the toxic chemical was of high purity. The latter is concluded from the almost complete absence of impurities.

12. The name and structure of the identified toxic chemical are contained in the full classified report of the Secretariat, available to States Parties.