Britain said that Russian Federation - in violation of chemical weapons treaties - has produced the Novichok class of nerve agents in the last 10 years.
In his first speech after a year as director of the Government Communications Headquarters, the British equivalent of the National Security Agency, Jeremy Fleming said the threat from Russia had "never gone away", but had become impossible to ignore after the poisoning of a former Russian spy and his daughter, cyberattacks on Ukranian infrastructure and other actions.
Sedwill also said that Russian Federation has tested means of delivering chemical agents "including by application to door handles", pointing out that the highest concentration of the chemical found after the attack was on Skripal's front door handle.
"The programme subsequently included investigation of ways of delivering nerve agents, including by application to door handles".
The strongest concentration of the Novichok nerve agent found in the Salisbury incident was on the front door of Mr Skripal's home.
The Organization for the Prohibition of Chemical Weapons says it has confirmed the U.K.'s findings on the identity of the poison used against a former Russian spy and his daughter last month.
The government of Prime Minister Theresa May expelled 23 Russian diplomats in retaliation and called on ir worldwide allies to follow in ir footsteps.
"As for "intelligence", it should be remembered that the United Kingdom has a vast record of misleading the government and the public, which entailed catastrophic consequences", the embassy said.
Skripal was a former Russian intelligence officer who acted as a double agent for MI6 and was caught, imprisoned, then pardoned and sent to Britain in a spy swap in 2010.
Sir Mark said Russian Federation failed to declare its work on Novichoks when it ratified the Chemical Weapons Convention. In her statement, she said that she has been made aware of the Russian embassy's attempts to contact her but she did not wish to avail of their services for the moment. The alleged hackers' attack is described as retaliation against London accusing Moscow of being involved in the Skripal case.
St Thomas's, in the centre of Salisbury, will hold the service at 3 p.m. on Sunday, metres away from the site of the bench where the Skripals were found outside the Maltings shopping centre.
It also received parts of samples taken by the British authorities which were analysed in OPCW-designated laboratories for "comparative purposes".
She also said she would give interviews to the media in time, but asked the press to have patience while she recovers.
Zakharova added there were doubts that a recent statement by Yulia Skripal was authentic.