Joe Biden has said Vladimir Putin has "no soul" and agreed when asked whether the Russian president is a "killer".
Putin will also face consequences for his interference in the 2020 elections, Biden, the US president, told ABC News host George Stephanopoulos in an interview aired on Wednesday morning.
His comments come after an intelligence report connected the Kremlin to online interference promoting Donald Trump during the 2020 presidential election.
The report, published on Tuesday, said that Putin and other senior officials "were aware of and probably directed" Russia's influence operation to sway the vote in Donald Trump's favour.
"He will pay a price," Biden said in the pre taped interview. Asked what the consequences could come for Putin, he replied "You'll see shortly."
"We had a long talk, he and I, when we - I know him relatively well - and the conversation started off, I said, 'I know you and you know me. If I establish this occurred, then be prepared."
The report, however, concluded that the election results were not compromised. The Kremlin has denied the claims.
Biden added that he believed Putin was a "killer", responding "I do" to Stephanopoulos's questioning.
He recalled telling Putin he didn't "have a soul" during a meeting with the leader.
"He looked back at me and said, 'We understand each other'," Biden said.
After Biden's victory overTrump in 2020, Putin was among the last world leaders to congratulate the newly elected president.
As he reaches his 50th day in office, the US president's extensive interview also covered the thousands of children arriving at the US border with Mexico, as well as the politicisation of the coronavirus vaccination.
He then addressed relations with Saudi Arabia following the killing of journalist Jamal Khashoggi and calls among Democrats for New York Governor Andrew Cuomo to resign.