In a special statement to the House of Commons, Prime Minister Theresa May revealed the two suspects flew into Britain to murder former Russian double agent Sergei Skripal and his daughter Yulia Skripal who lived in the town of Salisbury.
British prosecutors charged two Russians for the attempted murder of a former Russian spy and his daughter with a nerve agent, naming suspects for the first time in a case that has caused one of the biggest East-West rifts in decades.
The Kremlin denied that Russia had been in any way involved in the poisoning, describing British accusations that an attack had been approved by senior Russian officials as "unacceptable".
Prime Minister Theresa May said the use of a chemical weapon in the city of Salisbury, which left a British woman dead and four people, including Skripal and his daughter, seriously ill, was carried out by officers of the GRU intelligence service and nearly certainly approved "at a senior level of the Russian state".
Prime Minister Theresa May told lawmakers that British intelligence has concluded that the two men are officers of Russia's GRU military intelligence service.
Prosecutors can not apply to Russian Federation for the men to be extradited because Russian Federation does not have extradition agreements with the UK.
Russian Foreign Ministry spokeswoman Maria Zakharova told the media, Wednesday, that the names of the two men mean nothing to them, and urged the British government to work with them, instead of resorting to "information manipulations".
Police also want to lay charges of using a chemical weapon contrary to the Chemical Weapons Act.
"The UK is concerned about the activities of the Russian government, not Russian people", - said in another message of the Embassy.
Victoria said she did not know the suspects, and thanked Russian authorities and Putin personally for helping her.
"We can not account for the whereabouts of the bottle, nozzle or box between the attack on the Skripals on March 4 and when Charlie Rowley said he found it on Wednesday June 27". Basu said the passports were genuine but the names were probably aliases, and appealed to the public to help identify the men.
Police said they were liaising with prosecutors about further charges in connection with the death of Ms Sturgess and the poisoning of Mr Rowley.
London and its allies expelled dozens of Russian diplomats after the poisoning, prompting a tit-for-tat response from Moscow and plunging relations to a new low. Looking at the seriousness in the matter, May has thus called an emergency session of the United Nations Security Council on Thursday and will ask world leaders to back Britain's stand against Russian Federation.
Police released security camera images of the two suspects and outlined a three-day mission that took them from Moscow to London to Salisbury, where they sprayed poison on Skripal's door before flying back to Moscow hours later.
It was also confirmed that officers have now linked the attack on the Skripals to events in Amesbury four months later which killed Dawn Sturgess, 44, and made her 48-year-old partner, Charlie Rowley, seriously ill.
Mrs May nonetheless sought to further ramp up global pressure on Moscow, vowing to deploy "the full range of tools across our national security apparatus" to counter the threat posed by the GRU.
The Skripals continue to be in an undisclosed location since their discharge from hospital after the attack.