President Barack Obama avoided directly criticizing President-elect Donald Trump over his refusal to accept intelligence on Russian hacking, but suggested Republican politicians, media outlets — and even voters — put partisanship over country by failing to confront Trump’s warm praise for Vladimir Putin.

Obama made an apparent reference to a widely-shared Economist-YouGov poll showing 35% of Trump voters held a favorable of Putin — a massive shift towards the Russian leader over the last two years — as evidence the party had abandoned its normally hawkish stance on Russia out of partisanship.

Related: Obama Says the U.S. Will Send 'Clear Message' to Russia on Hacks

He chastised Republicans who had criticized his own administration for being too deferential to Putin only to endorse Trump, who repeatedly called for warmer relations with Russia and defended Putin from accusations of human rights abuses.

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"Over a third of Republican voters approve of Vladimir Putin, the former head of the KGB," Obama said. "Ronald Reagan would roll over in his grave."

Trump has dismissed intelligence findings from the CIA — now shared by the FBI — that Russia hacked Democratic emails to help his campaign, and appears to view the conversation around the issue as an effort to preemptively delegitimize his election. He falsely accused the White House this week of waiting to raise the issue after the election (the intelligence community publicly accused Russia of hacking the DNC in October).

Seemingly sensitive to those concerns, Obama was careful not to question Trump’s victory, saying that he was confident the election was conducted fairly and without any interference in the voting process itself. He also declined to say whether the political fallout over the hacks, as well as FBI director James Comey’s October letter reintroducing Hillary Clinton’s emails into the race, decided the election.

Obama said he had a “cordial” relationship with Trump during the transition and would continue to make himself available for advice.

But he also defended both the intelligence findings on Russia and suggested Trump should avoid making them a “partisan issue.”

“My hope is that the president-elect is going to similarly be concerned with making sure we don’t have potential foreign influence in our election process,” he said.

He added Trump was “still in transition mode from campaign to governance,” and suggested waiting to see how he performed as president with a full team in place before judging his foreign policy.

Obama also defended his own response to the hacks, which some critics have complained was too muted to deter Russia or to convey the magnitude of the issue to voters. He said he personally told Putin to “cut it out” in September, but avoided a more public retaliation because it “would have become one more political scrum” in the heat of the election. He did warn Russia, however, that “we can do stuff to you.”

Adopting the professorial style that often characterized his presidency, Obama blamed a variety of actors for magnifying the damage caused by the hack, especially partisan actors who seized on the leaks to attack Democrats, or passed on dubious claims from foreign sources, and the press for focusing coverage on stolen material rather than other topics.

“Our vulnerability to Russia or any other foreign power is directly related to how divided, partisan, dysfunctional our political process is,” he said.