British Prime Minister Theresa May will chair a meeting of Britain's National Security Council on Monday to discuss the poisoning of a former Russian double agent and his daughter.
Former double agent Sergei Skripal, 66, and his daughter Yulia, 33, have been in hospital in a critical condition since March 4 when they were found unconscious on a bench outside a shopping center in the southern English city of Salisbury.
Hundreds of people who visited the Zizzi restaurant or the Bishop's Mill pub in the normally quiet cathedral city were told on Sunday to wash their clothes after traces of nerve agent used to attack Skripal were found at both sites.
British counterterrorism police say a nerve agent was used against Skripal and his daughter but have not made public which one.
British Foreign Secretary Boris Johnson has warned that if Russia was behind the poisoning of Skripal, a former colonel in GRU military intelligence, than Britain would respond robustly.
Johnson also drew parallels between the poisoning of Skripal and the murder of former KGB agent Alexander Litvinenko who died in London in 2006 after drinking green tea laced with radioactive polonium-210.
Since Skripal was found slumped on a bench in Salisbury, Russia has repeatedly denied any part in his poisoning and says Britain is whipping up anti-Russian hysteria. Russia holds a presidential election on March 18.
Source: News Agencies, Edited by website team