"The speed at which the anti-Russian campaign was launched causes bewilderment", Putin said from Turkey, where he met with President Recep Tayyip Erdogan.
Countries around the world joined Britain in expelling diplomats in a sign of unity against the actions of Russian Federation.
On Saturday, Russian Foreign Ministry spokeswoman, Maria Zakharova, wrote on Facebook that more than 50 diplomats and staff members of the United Kingdom diplomatic mission in Russia would have to return to the United Kingdom in order to maintain the parity in the number of diplomatic personnel of the two countries.
That approach will mean that, among other countries affected, France, Germany and Poland would each have four of their diplomats in Moscow sent home, Ukraine would forfeit 13 diplomats, and Denmark, Albania and Spain would each have two of their embassy staff expelled.
Mr Filatov said on Tuesday the "whole story" put forward by the British government was still unclear and he said the questions Russian Federation was seeking answers to were "not meant to be rhetorical".
Russian Federation denies responsibility and has suggested the poison may have come from Britain.
Aitkenhead then hinted towards the involvement of a state actor in the manufacturing of the nerve agent, while pointing out at the sophisticated methods deployed in the manufacturing of the poisonous agent.More news: Foreign min denies Israel migrant deal (4)
Aitkenhead said the British government had "other inputs" it could use to determine the origin of the nerve agent, some of them intelligence-based.
On Tuesday, the Organization for the Prohibition of Chemical Weapons said it would hold an emergency meeting on the case at the request of Russian Federation, which is demanding Britain hand over its evidence.
The OPCW (Organisation for the Prohibition of Chemical Weapons) said its executive council would meet in the morning in The Hague. "As the Prime Minister has set out in a number of statements to the Commons since 12 March, this includes our knowledge that within the last decade, Russia has investigated ways of delivering nerve agents probably for assassination - and as part of this program has produced and stockpiled small quantities of Novichoks; Russia's record of conducting state-sponsored assassinations; and our assessment that Russia views former intelligence officers as targets". The organization says the meeting will be held at 0800GMT Wednesday.
Scientists at the U.K's Porton Down lab previously identified the poison as a Soviet-developed type of nerve agent known as Novichok.
Lavrov also assailed the British authorities for stonewalling Russia's request for consular access to Yulia Skripal, 33, a Russian citizen whose condition has improved since she and her father fell critically ill on March 4. "We identified that it is from this particular family and that it is a military grade, but it is not our job to say where it was manufactured".
He argued that experts have said that such nerve agents could have been made in some 20 countries. Moscow vehemently denies its responsibility. S., Canada, Albania, Norway and Ukraine, have announced their decisions to collectively expel over 150 Russian diplomats as a sign of solidarity with London on the Skripal case.
Russian Deputy Foreign Minister Alexander Grushko called the poisoning a "provocation arranged by Britain" in order to justify high military spending because "they need a major enemy".