"We know who they are, we have found them", the premier said at an economic forum in Vladivostock.
Britain last week charged the two Russians they allege are Russian military intelligence agents in absentia with the poisoning of former Russian spy Sergei Skripal and his daughter Yulia. "There's nothing particularly even criminal about them, I assure you", he said, adding they were "civilians, of course".
Scotland Yard has issued a European arrest warrant for the two men, who have not been seen publicly since the March attack.
The two suspects named by the United Kingdom as being behind the Novichok poisonings have been found in Russian Federation.
The Metropolitan Police published the suspects' photos, saying their names were Alexander Petrov and Ruslan Boshirov.
CCTV footage from early March shows the pair arriving at Heathrow Airport from Russian Federation, and also in the vicinity of Sergei Skripal's house on the day of the attack.More news: Jack Butland happy to live dangerously in Gareth Southgate's England system
More news: Henry Cavill is reportedly no longer playing Superman in the DC movies
More news: Donald Trump to order sanctions against countries that interfere in USA elections
"I hope they will soon appear and tell their own story", Putin added with a smirk during a meeting with Japanese Prime Minister Shinzo Abe and China's Xi Jinping. We know who they are, we have found them already.
Rowley in July unwittingly picked up a fake perfume bottle, which the perpetrators filled with nerve agent meant to poison Skripal and made to look like it was from a designer brand.
Russian Federation adamantly denies involvement in the poisoning, which had added to severe strains in ties between Russian Federation and the West.
Mr Skripal and his daughter were left in a critical condition after they were exposed to Novichok but are now recovering.
Reacting to Mr Putin's assertion that the spies were civilians, Theresa May's spokesman said Russian Federation has continually replied to requests for an account of what happened in Salisbury with "obfuscation and lies" and he could see "nothing to suggest that has changed".
He accused Britain of attempting "to unleash a disgusting anti-Russian hysteria". Mr. Rowley gave it to his girlfriend, Dawn Sturgess, who later died.
Britain and dozens of other countries kicked out scores of Russian diplomats over the poisoning of the Skripals, and Moscow responded tit-for-tat with an identical number of expulsions.