"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 and we will at a time and place of our own choosing," Obama told National Public Radio.
Describing potential countermeasures by the U.S., the President said "some of it may be explicit and publicized; some of it may not be."
He said he directly confronted Russian President Vladimir Putin about a potential US response, and said his counterpart acknowledged his stance.
"Mr. Putin is well aware of my feelings about this, because I spoke to him directly about it," Obama said.
Obama and Putin conferred on the sidelines of the G20 meeting in China in September. Afterwards, Obama told reporters he raised cybersecurity with the Russian leader.
Intelligence agencies in October pinned blame on Russia for election-related hacking. At the time, the White House vowed a "proportional response" to the cyberactivity, though declined to preview what that response might entail.
Officials have said U.S. actions against Russia may not be revealed publicly.