London/New York, Jumada II 27, 1439, March 15, 2018, SPA -- Russia accused Prime Minister Theresa May of creating a "hysterical atmosphere" after she expelled 23 of its diplomats from Britain in retaliation for a nerve agent attack that London believes was orchestrated by Moscow. Britain announced the expulsion of the diplomats and cancelled an invitation for a visit by Russian Foreign Minister Sergei Lavrov in response to the poisoning of a former Russian spy on British soil. The measures are part of a "full and robust" answer to the use of a Russian-developed nerve agent to poison the former double agent and his daughter, and Moscow's refusal to account for the presence of the toxin, May told parliament on Wednesday, according to dpa. At an emergency meeting of the UN Security Council in New York called by Britain, Russia's UN Ambassador Vassily Nebenzia said May was creating a "hysterical atmosphere." "We do not speak the language of ultimatums," Nebenzia said, referring to May's summoning of Russia's ambassador to demand an explanation. There is no proof behind the "egregious" allegations contained in a letter sent by May to the Security Council president and UN secretary general, Nebenzia said. Nebenzia then suggested that perhaps fictional British detective Sherlock Holmes would be better placed to carry out an investigation than London's Scotland Yard. Russia's "denial, distraction and threats" will not deter Britain, its UN ambassador Jonathan Allen said, adding that there was "no alternative conclusion" than that Russia was responsible for the attack. In Paris, Foreign Minister Jean-Yves Le Drian said France would shortly coordinate with Britain on its response to the poisoning. "In the coming hours, France will be in contact with British authorities at the highest level to coordinate our response," Foreign Minister Jean-Yves Le Drian said after a meeting with his German counterpart Heiko Maas. European security and "the security of one of our principal allies" was at stake, Le Drian said. Former Russian spy Sergei Skripal, 66, and his daughter Yulia, 33, remain critically ill in hospital after they were found unconscious last week on a bench in the southern English town of Salisbury. The elder Skripal was convicted of selling Russian state secrets to Britain in 2006 and traded to Britain in a high-profile spy swap a few years later. Britain has identified the nerve agent as one of a class of chemical warfare agents known as Novichoks, which Russia inherited from the Soviet Union. Russia is in breach of the chemical weapons convention for not declaring the Novichok programme, Allen said. In addition to the diplomatic measures, Britain announced it will send no senior officials or members of the royal family to the football World Cup in Russia this year, suspending "all planned high-level contacts" between London and Moscow. Russia vowed to quickly retaliate against Britain for the expulsions, condemning the British measure as an "unprecedentedly crude provocation" conducted "under a false pretext." Britain's actions are "destroying the foundations of normal intergovernmental dialogue between our countries," Russia's Foreign Ministry said in a statement. May said the 23 diplomats had been given one week to leave Britain after they were "identified as undeclared intelligence officers." "This will be the single biggest expulsion for over 30 years, and it reflects the fact that this is not the first time that the Russian state has acted against our country," she said, citing the poisoning of another former Russian spy, Alexander Litvinenko, who died in 2006. Litvinenko became critically ill after drinking tea laced with a radioactive isotope. A British inquiry concluded that he was targeted for assassination by Russian agents. May told parliament that Russia's response to the Skripal case has "demonstrated complete disdain for the gravity of these events." "They have provided no credible explanation that could suggest they lost control of their nerve agent," May said. "No explanation as to how this agent came to be used in the United Kingdom, no explanation as to why Russia has an undeclared chemical weapons programme in contravention of international law." "Instead they have treated the use of a military-grade nerve agent in Europe with sarcasm, contempt and defiance," she said. --SPA 02:58 LOCAL TIME 23:58 GMT www.spa.gov.sa/w642119