The UK government says they were poisoned with a nerve agent of a type developed by Russian Federation called Novichok.
In retaliation, Kiev said Russians living in Ukraine will not be able to vote as access to Moscow's diplomatic missions will be blocked.
The Russian Foreign Ministry also said in a statement that it is ordering the closure of the British Council, a government organisation for cultural and scientific cooperation, and that it is ending an agreement to reopen the British consulate in St Petersburg.
A tent covers the park bench where former Russian intelligence agent Sergei Skripal and his daughter Yulia were found after they were poisoned, in Salisbury, Britain. He suggested that would have been the only way for British authorities to identify the nerve agent so soon after Mr. Skripal and his daughter collapsed.
The Foreign Office said there was "not an ounce of truth" in Mr Chizhov's suggestion of a link to Porton Down.
The British Council said it was profoundly disappointed by Russia's decision and remained committed to developing long-term people-to-people links with Russian Federation despite the closure.
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Neither has been accused of wrongdoing but they made their money during the chaotic years following the breakup of the Soviet Union when state assets were transferred to private ownership. And it said it had halted the activities of the British Council, Britain's worldwide organisation for cultural relations and educational opportunities. It ordered the diplomats to leave within a week.The statement said the government could take further measures if Britain takes any more "unfriendly" moves toward Russian Federation.
Incumbent leader President Vladimir Putin is expected to win today's elections, despite facing seven challengers.
Mr. Skripal's poisoning has set off an angry confrontation between Britain and Russian Federation.
"In case of further unfriendly actions against Russia, the Russian side reserves the right to take further retaliatory measures - this is what the British Ambassador was told on Saturday", he said.
The foreign secretary said officials from the Netherlands-based Organization for the Prohibition of Chemical Weapons would arrive in Britain on Monday to take samples of the nerve agent used to poison the Skripals.
Associated Press writer Angela Charlton in Moscow contributed.
She said that in post-Soviet times it is countries such as the UK, Slovakia, the Czech Republic, Sweden, and possibly the USA, that studied the substance with keen interest and could have been the origin for the toxin used in the poisoning of Sergei Skripal and his daughter, Yulia.
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London has asked Moscow to explain the use of a military-grade nerve agent for the poisoning in England of Skripal and his daughter and United Kingdom police and the Security Service (MI5) said that they were pursuing 14 suspicious death cases that may lead to the Russian government.
But a Russian scientist disclosed details of a secret program to manufacture the military-grade nerve agents in the 1990s, and later published the formula. Topping the list was Britain itself - the other three, Slovakia, the Czech Republic and Sweden.
Czech Foreign Minister Martin Stropnicky said this was "wholly unsubstantiated" and "highly speculative". A policeman who was among the first to try to help the pair is still hospitalized but is now in stable condition.
Some 145,000 observers were monitoring the voting in the world's largest country, including 1,500 foreigners and representatives from opposition leader Alexei Navalny's movement, and they and ordinary Russians reported hundreds of voting problems.
British toxicologists say Novichok was used in the assassination attempt.
Russian Federation also suspects foul play in Glushkov's death and opened its own inquiry Friday.
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Lawless contributed from London.