President Trump questioned Monday whether Russia was behind the 2016 hacking of the Democratic National Committee's emails. 

Trump spoke at a joint press conference with Russian President Vladimir Putin in Helsinki, Finland, after the two met for almost two hours behind closed doors.

"Who do you believe?" Associated Press reporter Jonathan Lemire asked Trump, pointing out that U.S. intelligence agencies have concluded Russia was behind the hacks. 

He asked whether Trump "with the whole world watching" would "denounce" Russia's actions and warn Putin to never do it again. 

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“I have great confidence in my intelligence people,” Trump said Monday. “But I will tell you that President Putin was extremely strong and powerful in his denial today.”

Deputy Attorney General Rod Rosenstein announced on Friday the indictment of 12 Russian intelligence officers for hacking emails from the Hillary Clinton campaign and Democratic Party during the 2016 election.

The president added that Putin offered to question the officers who were indicted, and that Special Counsel Robert Mueller and his team could be present for it.

"That's an incredible offer," Trump said.

Trump emphasized that the DNC server was never taken by the FBI, adding that he has been asking why the agency was asked to leave the DNC's office.

"Where is the server?" he asked. "I want to know -- where is the server and what is the server saying?"

Furthermore, the president questioned the whereabouts of Hillary Clinton's personal email server, and of the former IT aide to congressional Democrats, Imran Awan.

Earlier in the press conference, Trump called the Mueller probe "ridiculous."

Watch the remarks above.

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