Trump repeatedly expressed admiration and respect for Putin throughout his campaign.
On Sept. 7, Trump said Putin had been a leader of his own nation "far more" than President Barack Obama had been of the United States, adding that Putin "has very strong control over a country. Now, it's a very different system and I don't happen to like that system."
Trump said repeatedly during the campaign that he had no relationship with Putin, but in a 2013 interview he said "I do have a relationship with Putin ..."
There have also been multiple reports linking Trump's business interests to Russia. Trump's son, Donald Trump Jr., told Russian daily Kommersant that "Russians make up a pretty disproportionate cross-section of a lot of our assets," adding that "we see a lot of money pouring in from Russia."
Vladimir Putin runs Russia as virtual dictator, and the country has no legally guaranteed freedoms.
Russia fomented a civil war in neighboring Ukraine and annexed one of its provinces after Ukraine kicked Yanukovych out of office and put pro-Western leadership in his place.
—The Associated Press contributed to this report.