Obama told in an interview with CBS News, that President-elect Joe Biden had "clearly won" this year's race for the White House.
Mr Obama claimed all the allegations were driven by the fact that "the president doesn't like to lose".
"They appear to be motivated, in part, because the President doesn't like to lose, and never admits loss," he said. "I'm more troubled by the fact that other Republican officials, who clearly know better, are going along with this," he added. "It's one more step in delegitimising, not just the incoming Biden administration, but democracy generally, and that's a dangerous path."
Obama's comments came as Trump continues to question the legality of vote counting in key battlefield states that are under scrutiny. Meanwhile, Republican leaders in Congress have urged Trump to stand aside despite the reported election fraud.
Before the official result of the election race, Obama congratulated President-elect Joe Biden and his running mate, Kamala Harris, on their win, addressing a statement on Twitter.
Must see @seanhannity takedown of the horrible, inaccurate and anything but secure Dominion Voting System which is used in States where tens of thousands of votes were stolen from us and given to Biden. Likewise, the Great @LouDobbs has a confirming and powerful piece!— Donald J. Trump (@realDonaldTrump) November 13, 2020