Sergei Skripal, 66, and his daughter Yulia, 33, are in a critical condition in hospital Photo: EPA/ YULIA SKRIPAL/FACEBOOK[/caption]
Moscow must explain why a Russian-made nerve agent was used in the poisoning of former Russian agent Sergei Skripal and his daughter by the end of Tuesday, Theresa May said.
The PM said it was “highly likely” Russia was responsible for the attack in Salisbury, Wiltshire, on 4 March. Nato secretary-general Jens Stoltenberg said: “The UK is a highly valued ally, and this incident is of great concern to Nato.” Russia called the claims “unfounded”. US Secretary of State Rex Tillerson said it appeared the “really egregious act… clearly came from Russia” and there should be “serious consequences”. Home Secretary Amber Rudd will chair a meeting of the government’s emergencies committee Cobra later to discuss the case. Former double agent Mr Skripal, 66, and his daughter, Yulia, 33, were found slumped on a bench in Salisbury city centre. They remain in a critical but stable condition in hospital. Det Sgt Nick Bailey, who fell ill attending to the pair, remains seriously ill, but has been talking to his family. Mrs May told the Commons on Monday that the poison used in the attack was a military-grade nerve agent developed by Russia. She said it was part of a group of nerve agents known as Novichok. “Either this was a direct action by the Russian state against our country, or the Russian government lost control of its potentially catastrophically damaging nerve agent and allowed it to get into the hands of others,” she said. Mrs May said the Foreign Office had summoned Russia’s ambassador to “explain which of these two possibilities it is”. She warned that if there was no “credible response” by the end of Tuesday, the UK would conclude there has been an “unlawful use of force” by Moscow.
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Theresa May: Spy poisoned by “military-grade nerve agent”[/caption]

‘Really egregious act’
Mr Tillerson, who spoke to Foreign Secretary Boris Johnson on the phone about the case on Monday, said the US supported the UK’s assessment that Russia was likely responsible.
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President Vladimir Putin is asked whether Russia had a hand in the Skripal poisoning[/caption]


What are Novichok agents?

- The name means “newcomer” in Russian, and applies to a group of advanced nerve agents developed in secret by the Soviet Union in the 1970s and 1980s
- One chemical – called A-230 – is reportedly five to eight times more toxic than VX nerve agent, which can kill a person within minutes
- Some are liquids, others are thought to exist in solid form. Some are reported to be “binary weapons”, meaning they are typically stored as two less toxic chemicals which when mixed, react to produce the more toxic agent
- One variant was reportedly approved for use by the Russian military as a chemical weapon
- Designed to escape detection by international inspectors, their existence was revealed by defectors