The Russian president faces a backlash after suggesting minority groups, including Jews, may be responsible for meddling in the 2016 US election.
Vladimir Putin made the comments during a US TV interview with Megyn Kelly.
US lawmakers and Jewish groups are among those criticising him.
Some are publicly asking US President Donald Trump to push Mr Putin for a clarification on what he meant when questioning whether certain groups were actually Russian.
Mr Putin was being asked during the NBC interview about charges of alleged Russian meddling in the 2016 election after 13 nationals were charged by the US special counsel's office last month.
"I couldn't care less because they do not represent the government, I could not care less. They do not represent the interests of the Russian state," Mr Putin said.
"Maybe they're not even Russians, but Ukrainians, Tatars, Jews, just with Russian citizenship. Even that needs to be checked.
"Maybe they have dual citizenship. Or maybe a green card. Maybe it was the Americans who paid them for this work. How do you know? I don't know."
'Classic anti-Semitic stereotypes'
Mr Putin has been criticised by some groups, including the Anti-Defamation League (ADL).
"President Putin bizarrely has resorted to the blame game by pointing the finger at Jews and other minorities in his country," ADL chief executive Jonathan Greenblatt said in a statement.
"It is deeply disturbing to see the Russian president giving new life to classic anti-Semitic stereotypes that have plagued his country for hundreds of years, with a comment that sounds as if it was ripped from the pages of the Protocols of the Elders of Zion."
The comment refers to a work of fiction published in a Russian newspaper in 1903, which was used to justify propaganda that there was a Jewish conspiracy to take over the world.
US Senator Richard Blumenthal said the "repulsive" remark should be denounced by world leaders.
Repulsive Putin remark deserves to be denounced, soundly and promptly, by world leaders. Why is Trump silent? Intolerance is intolerable. https://t.co/ZxQHvIWs5w— Richard Blumenthal (@SenBlumenthal) March 10, 2018
Julia Davis, a Russian media analyst, said the comments made clear that Mr Putin only considers "ethnically Russian" people nationals, which she labelled a "disturbing distinction".
Others suggested that Mr Putin was not blaming any group for the interference comments, rather just dismissively running through a list.
The American Jewish committee has said that Mr Putin should clarify the comments "at the earliest opportunity".