Two Russians accused by London of trying to kill a former double agent with nerve agent posed as businessmen to obtain visas to visit Britain for the attack, a report said Friday.
British authorities have issued European arrest warrants for Alexander Petrov and Ruslan Boshirov, two suspected members of Russian military intelligence.
They are accused of trying to kill former Russian spy Sergei Skripal and his daughter Yulia with Novichok in the English city of Salisbury on March 4, in an attack London believes was sanctioned by the Kremlin.
The Daily Telegraph newspaper, citing an unnamed security source, said the two men had posed as businessmen to obtain their visas from the British consulate in Saint Petersburg.
They reportedly told authorities they were working in international trade, and both produced business cards as well as details of their bank accounts to prove they had the necessary assets for a visa.
Police say the men travelled on Russian passports bearing the names Petrov and Boshirov, but that these are almost certainly aliases. The Telegraph said their true names were known to the security services.
The Skripals recovered, as did a British policeman who fell ill after working on the case.
But a fake perfume bottle containing Novichok was picked up weeks later by a local man, Charlie Rowley, who give it to his girlfriend, Dawn Sturgess. They both became ill and she later died.
The British government has said Russian President Vladimir Putin is ultimately responsible for the attack, something Moscow has strongly denied.
The United States, Canada, France and Germany on Thursday issued a statement supporting the analysis that two Russian agents were responsible for the poisoning.
And at the UN Security Council a few hours later, where Britain laid out its findings, US Ambassador Nikki Haley said everyone should be "chilled to the bone" by what happened.
However, Russian ambassador Vassily Nebenzia accused Britain of spreading "the same repeated lies" and presenting an "unfounded mendacious cocktail of facts.
"The Russian Federation categorically rejects all unfounded accusations regarding its involvement," he said.
After the attack in March, Britain and its allies expelled dozens of Russian diplomats, prompting Moscow to respond in kind, while the United States later introduced sanctions in relation to the incident.
In a speech in Washington late Thursday, the head of Britain's GCHQ spy agency said the threat from Russia would be "countered by a strong international partnership of allies".
They are "able to deploy the full range of tools from across our national security apparatus. And ready to reject the Kremlin's brazen determination to undermine the international rules-based order".