Addressing claims Russian Federation orchestrated the nerve agent attack on Skripal, an ex-KGB agent who handed secrets to M16, Lavrov insisted: "There is no motive at all".
Russian Federation also said that it was withdrawing permission for Britain to operate its consulate in the North western city of Saint Petersburg, citing a "disparity" in the number of diplomatic missions held by the two countries.
Britain will expel almost two dozen Russian diplomats, sever high-level bilateral contacts with Moscow and take both open and covert action against Kremlin meddling after the poisoning of a former spy, the prime minister said Wednesday, plunging United Kingdom.
It said: "Clearly, by employing unilateral and non-transparent methods to investigate this incident, British authorities once again attempted to launch a baseless campaign against Russian Federation".
The Russian Ministry of Foreign Affairs said in a statement Saturday that 23 British diplomats are "persona non grata" and must leave the country within a week.
Prime Minister Theresa May told Parliament Wednesday that there was "no alternative conclusion other than that the Russian State was culpable" in the attack, and later ordered the expulsion of 23 Russian diplomats.
Russian Federation has said it is open to cooperation with Britain, but has refused Britain's demands to explain how Novichok, a nerve agent developed by the Soviet military, was used against the Skripals.
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USA government chemical warfare experts are also working closely with their British counterparts on what is a major investigation. This is not the first time the USA media have reported updates from intelligence officials about incidents in the UK.
Russia has repeatedly denied any involvement, casting Britain as a post-colonial power unsettled by Brexit, and even suggested London fabricated the attack in an attempt to whip up anti-Russian hysteria.
The Trump administration announced Friday in an unrelated matter that the US was imposing sanctions on Russian entities and individuals, including Russian spy agencies, for meddling in the 2016 presidential election and waging cyberattacks against the U.S. They have been in a critical condition in hospital ever since.
UN Security Council had an emergency session on March 14, when Great Britain confirmed that Russian Federation used Novichok agent to poison Skripal and his daughter.
The ministry also revoked its agreement on opening and operation of the UK Consulate General in the Russian city of St. Petersburg, according to the statement.
She had to battle with the British authorities to hold the public inquiry into her husband's death, which May - then interior minister - had initially ruled out as Britain sought better relations with Russian Federation.
Shadow chancellor John McDonnell said the Salisbury incident is "highly likely" to have been a state execution, and Russian president Vladimir Putin "is responsible" for the attack whether directly or through negligence.
Putin is expected to easily win a presidential election on Sunday which would bring him to almost a quarter of a century in power.