The evidence that Russia is hiding behind the chemical attack on Sergei Skripal and his daughter in Salisbury is overwhelming, said British Foreign Secretary Boris Johnson.
Speaking to the BBC on Thursday morning, Mr Johnson said the former Russian double agent had been the subject of "revenge and retaliation" for the Kremlin. He reiterated that the substance used, of the Novitsok family of gaseous nerves, is made only in Russia.
He also criticized Russia's "sarcastic" response to the British allegations.
Mr Johnson was speaking after a special meeting of the United Nations Security Council in which Russia accused Britain of failing to provide evidence to support the allegations.
The British side responded that it has been asked by the Organization for the Prohibition of Chemical Weapons to verify the findings of the investigations that have been carried out.
The Foreign Secretary also stressed the international support that Britain has received, including at yesterday's tense meeting of the Security Council.
As for Russia's response to the anti-Moscow measures announced by Prime Minister May, Boris Johnson said that this is a matter for the Russians and that the British government considers that it has reacted in a way that suits the occasion.
He noted, however, that Britain must continue to talk to Russia, "as in the darkest days of the Cold War."
Russian Foreign Ministry spokeswoman Maria Zakharova reiterated that Moscow had requested but had not received samples of the substance, which the British claimed to have detected in Salisbury. He also spoke of Britain's "political show" at the United Nations and the rupture of Russia's confidence in Britain as an international partner.
Meanwhile, British Defense Secretary Gavin Williamson will announce today the launch of a vaccination program for the country's soldiers to protect them from carbon offensive attacks.
At the same time, the British representative will inform NATO in Brussels about the details of the Skripal case.