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President Barack Obama said Thursday the United States will retaliate against Russian hacking aimed at interfering in the US election, after a White House official claimed President Vladimir Putin was involved.

"I think there is no doubt that when any foreign government tries to impact the integrity of our elections that we need to take action," Obama told NPR radio.

"And we will, at a time and place of our own choosing."

"Some of it may be explicit and publicized," the president added. "Some of it may not be."

NPR said Obama avoided endorsing a CIA conclusion that Russia hacked into email accounts of Democratic Party institutions and officials with the specific goal of hurting the party's candidate Hillary Clinton and helping Republican Donald Trump win the election.

Obama has ordered US intelligence agencies to conduct a full review of the hacking and report back to him before he leaves office on Inauguration Day January 20.

"There are still a whole range of assessments taking place among the agencies," Obama told NPR.

The full interview is set to air Friday morning, hours before Obama is scheduled to give a year's end news conference.

"And so when I receive a final report, you know, we'll be able to, I think, give us a comprehensive and best guess as to those motivations," Obama said.

Earlier on Thursday, Ben Rhodes, a top advisor to Obama, told MSNBC television "I don't think things happen in the Russian government of this consequence without Vladimir Putin knowing about it."

"Everything we know about how Russia operates and how Putin controls that government would suggest that, again, when you're talking about a significant cyber intrusion like this, we're talking about the highest levels of government," he said.

"And ultimately, Vladimir Putin is the official responsible for the actions of the Russian government."

President-elect Donald Trump for his part rejected the accusations that Russia had hacked the elections to influence the outcome.

"If Russia, or some other entity, was hacking, why did the White House wait so long to act? Why did they only complain after Hillary lost?" he tweeted.

But the 70-year-old billionaire-turned-president-elect appeared increasingly isolated in his stance as the scandal posed a deep challenge to his aim of resetting Washington's strained relations with Moscow.

The conclusions by key intelligence bodies including the CIA and the FBI have been accepted throughout the government, including among top members of Trump's Republican Party.

On Wednesday, senior Republican Senator Lindsey Graham said he was informed by the FBI in August that his own campaign had been hacked.

Former CIA director Michael Hayden called Trump "the only prominent American that has not yet conceded that the Russians conducted a massive covert influence campaign against the United States."

"On this particular event, what Mr Trump says about it is the same thing that Mr Putin says about it," he told CNN Wednesday.

The Kremlin rejected the allegations of Putin's involvement.

"Ridiculous nonsense cannot have any basis," his spokesman Dmitry Peskov told journalists Thursday.