TEMPO.CO, London - Britain is to kick out 23 Russian diplomats, the biggest such expulsion since the Cold War, over a chemical attack on a former Russian double agent in England that Prime Minister Theresa May blamed on Moscow, an assessment backed by the United States.

May pointed the finger firmly at Russian President Vladimir Putin on Wednesday as she outlined retaliatory measures in parliament.

Russia denies any involvement in the attack on ex-spy Sergei Skripal and his daughter Yulia, who have been critical in hospital since they were found unconscious on March 4 on a bench in the city of Salisbury.

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May announced the potential freezing of Russian state assets that pose a security threat, new laws to counter hostile state activity and a downgrading of Britain’s attendance at the soccer World Cup in Russia this summer.

She had given Moscow until midnight on Tuesday to explain how the Soviet-made Novichok nerve agent came to be deployed on the streets of Salisbury, saying either the Russian state was responsible or had lost control of a stock of the substance.

“Their response demonstrated complete disdain for the gravity of these events,” May said in her statement to parliament. “They have treated the use of a military-grade nerve agent in Europe with sarcasm, contempt and defiance.”

The only possible conclusion was that the Russian state was behind the attempted murder of the Skripals and the harm that befell Nick Bailey, a police officer who is in a serious condition after being exposed to the nerve agent, May said.

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“This represents an unlawful use of force by the Russian state against the United Kingdom,” she said.

The Russian Foreign Ministry said Moscow would swiftly retaliate against the British measures which had been undertaken for “short-sighted political ends”.

“The British government has made a choice in favour of confrontation with Russia,” it said.

Russia’s Ambassador to the United Nations, Vassily Nebenzia, repeated Moscow’s denial that it had anything to do with the poisoning and called for proof of its involvement.

REUTERS