US President Barack Obama said on Friday he had "great confidence" the hacking of Democratic Party officials and institutions were carried out by Russia and at the behest of high-level Russian officials.
"The intelligence that I've seen gives me great confidence in their assessment that the Russians carried out this hack," Mr Obama said at a White House news conference.
Mr Obama said he had warned Russian President Vladimir Putin in September to stop meddling in US political campaigns after hacks of Democratic Party emails in the lead-up to the November 8th elections.
‘Cut it out’
In a pre-Christmas holiday press conference, Mr Obama said he told Mr Putin to "cut it out" during a face-to-face encounter in China where a G20 meeting was being held.
Mr Obama added that after warning Mr Putin, there was no further evidence of Russian tampering.
Russia has denied US accusations of cyber attacks against US political figures and institutions ahead of the presidential and congressional elections.
Two senior government officials told Reuters that the FBI backs the CIA's view that Russia intervened to help Republican Donald Trump win the presidential election.
Mr Obama left open the door to US retaliation against Russia to discourage it and other nations from further computer hacking.
‘Political football’
The president said he hoped Mr Trump, who takes office on January 20th, should be similarly concerned about Russia’s actions and that the investigation should not become “a political football” between Republicans and Democrats.
Mr Trump has maintained that he won the election fairly and has bristled at suggestions that Moscow influenced the outcome.
But Democrats repeatedly noted Mr Trump during his campaign had spoken glowingly about Mr Putin and since winning the election has picked top aides in the incoming administration who have ties to Russia.
At one point during the heated presidential campaign, Mr Trump publicly encouraged Russia to hack Democratic rival Hillary Clinton’s emails.
Reuters