He and his daughter, 33, were found collapsed on a bench near a shopping mall Sunday in the town of Salisbury, 90 miles southwest of London.
Last night, it became known that 180 specialists in the chemical protection of the British Armed Forces were sent to disinfect potentially risky objects.
"In terms of further options, that will have to wait until we're absolutely clear what the consequences could be and what the actual source of this nerve agent has been", Rudd said.
They're tasked with removing vehicles and objects due to fears of contamination.
The figure includes members of the public and emergency staff, some of whom have had blood tests as well as receiving support and advice.
Police say they know the nerve agent used in the attack, but have declined to say what it was nor how they suspect it was administered.
Wiltshire Police undated handout photo of Detective Sergeant Nick Bailey who rushed to the aid of a Russian ex-spy targeted with a nerve agent.
TRT World's Sarah Morice has more.
The grave of Mr Skripal's wife Liudmila, who was buried in 2012, and the memorial stone of his son Alexander, who was cremated past year, were cordoned off at the London Road cemetery.
On Friday, police launched an inquiry in the cemetery where Skripal's Russian's wife and son were laid to rest. Officers were guarding the area where he and his daughter were found, along with a pizza restaurant and a pub they had visited. Commentators said police were exploring the theory that the former Russian spy and his daughter, who was reportedly visiting from Moscow, were exposed to the nerve agent at the house.
REUTERS Peter NichollsUK Police Say Identified Hundreds of Witnesses in Russian ex Spy Poisoning Case
The Times newspaper said British officials were talking to their U.S. and European counterparts about a co-ordinated retaliation, which could include "diplomatic, economic and military measures" if Moscow was behind the attack.
Sergei Skripal until 1999, was a Colonel in the GRU - the foreign intelligence body of the Ministry of defense of Russian Federation.
He was pardoned in 2010 before being flown to Britain.
"What we see is only news reports ... saying that if it is Russian Federation, then a response is going to be given that Russian Federation is going to remember forever", Mr Lavrov said during a visit to Addis Ababa.
Russian Federation has denied being behind the attack, but a presenter on state television warned this week that "traitors" that they should not settle in Britain or risk dying in "strange incidents".
Foreign minister Boris Johnson floated the deepening of sanctions against Russian officials, but Britain would have to convince its global partners.
It could also choose to impose sanctions of its own against the many Kremlin-linked officials with investments or family ties in London.
"But in order to conduct such cases, it is necessary not to immediately run out on TV screens with unfounded allegations", Russian Foreign Minister Sergey Lavrov was quoted as saying by Russian state news agency Tass. He further said, "The profession of a traitor is one of the most unsafe in the world".
"It is possible that it is related to the elections in Russia or that it is part of a battle between the elites within the security services, to send messages either to the English or to the Russian elites", he said.
Tommy Lee accuses adult son of assault
We're told Tommy shot back at Brandon , asking him why's he's upset by this but not upset that Pam accused him of abuse. Lee's fiancé Furlan later Tweeted , "Violence is NEVER the answer".
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