Trump and his allies have continued to challenge the results in court, insisting widespread fraud and other irregularities were responsible for his electoral defeat. But election officials from both parties have all publicly attested there was no mass malfeasance. And even if the president does score some legal victories, the wide margins in key swing states place the odds of reversing the election results at practically none.

Many of Trump's Republican allies in the Senate, House and his administration have refused to acknowledge Biden as the president-elect, claiming the election results were unclear. Emily Murphy, the Trump-appointed head of the General Services Administration, has also not yet recognized Biden as president-elect, which by law bars his transition team from formally going forward with his move to the White House.

During his interview, Obama said Trump's resistance of the results "appear to be motivated in part because the president doesn't like to lose." He added that he was "more troubled by the fact that Republican officials that clearly know better are going along with this."

Cindy McCain, the widow of Sen. John McCain, who ran against Obama in 2008, agreed with Obama's sentiment, saying her husband would be "very troubled" by Trump's refusal to accept defeat.

"It's dangerous for this to occur. It's time that the president get on the right side of history and make sure that our incoming president has all the things he needs to begin with his feet on the ground," McCain told CNN's Wolf Blitzer on Thursday.