US penalises Moscow over attempted slaying of ex-spy and daughter in UK and says more draconian measures could follow

The United States has announced it will impose restrictions on the export of sensitive technology to Russia because of its use of a nerve agent in the attempted murder of a former Russian spy and his daughter in Britain.

The state department said the new sanctions would come into effect on 22 August and would be followed by much more sweeping measures, such as suspending diplomatic relations and rescinding Aeroflot landing rights, if Russia did not take “remedial” action within 90 days.

Moscow is not expected to agree to the response required by US legislation, which includes opening up Russian scientific and security facilities to international inspections to assess whether it is creating chemical and biological weapons in violation of international law.

” Certainly is genuinely up to Russia to construct that decision, whether they meet this criteria ,” a senior administration official said.” The second round of sanctions … are in general more draconian than the first round .”

The US has already expelled 60 suspected Russian spies as part of a global response to the March attack in Salisbury against Sergei Skripal, a former colonel in Russian military intelligence, and his daughter, Yulia, in which a rare and potent Russian-made nerve agent , novichok, was found to have been used.

Quick guide

What is novichok?

Novichok refers to a group of nerve agents developed by the Soviet Union in the 1970 s and 80 s to evade international restrictions on chemical weapons. Like other nerve agents, they are organophosphate compounds, but the chemicals to benefit from make them, and their final structures, are considered classified in the UK, the US and other countries.

The most potent of the novichok substances are considered to be more lethal than VX, the most deadly of the familiar nerve agents, which include sarin, tabun and soman.

While the novichok agents work in a similar way, by massively over-stimulating muscles and glands, one chemical weapons expert said the agents did not degrade fast in the environment and had ‘an additional toxicity that was not well understood. Treatment for novichok exposure would be the same as for other nerve agents, namely with atropine, diazepam and potentially narcotics called oximes.

The chemical structures of novichok agents were made public in 2008 by Vil Mirzayanov, a former Russian scientist living in the US, but the structures have never been publicly corroborated. It is thought they can be made in different forms, including as a dust aerosol.

The novichoks are known as binary agents because they only become lethal after mixing two otherwise harmless components. According to Mirzayanov, they are 10 to 100 times more toxic than conventional nerve agents.

While laboratories that are used to police chemical weapons incidents have databases of nerve agents, few outside Russia are believed to have full details of the novichok compounds and the chemicals needed to stimulate them.

Photograph: Matt Cardy/ Getty Images Europe

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