Many Democratic leaders have backed Kamala Harris as the party's new US Presidential candidate, but ex-president Barack Obama has held off so far.
According to the New York Post, Obama hasn't endorsed Harris - who US President Joe Biden supported after he dropped out of the race on Sunday, as he doesn't think she can beat Republican candidate Donald Trump.
"Obama is very upset because he knows she can't win," a Biden family source told The New York Post.
"Obama knows she's just incompetent - the border czar who never visited the border, saying that all migrants should have health insurance. She cannot navigate the landmines that are ahead of her," the source said. "When you are running for president there are things you can and can't say."
The source said that Obama's hope was to get Biden out of the way and an article written by actor George Clooney, asking him to step aside, was a part of that plan.
Obama wanted Arizona Senator Mark Kelly "at the top of the ticket" when the Democratic National Convention is held next month, the source told The New York Post.
"Obama is furious, things haven't gone his way, which is why he is not joining in the Democratic Party's support of Harris," the source added.
However, NBC News reported on Thursday that Barack Obama plans to endorse Kamala Harris soon.
Obama privately has fully supported Harris' candidacy and has been in regular contact with her, the report said, citing people familiar with the discussions.
"Aides to Obama and Harris also have discussed arranging for the two of them to appear together on the campaign trail, though no date has been set," the report said.
Michelle Obama To Replace Joe Biden?
Earlier last month, before Joe Biden bowed out, US Senator Ted Cruz predicted that former First Lady Michelle Obama would replace him.
His prediction came after Biden's presidential debate against Donald Trump, which was widely criticised by political analysts.
"The odds are north of 80% that the Democratic Party will remove Joe Biden from the ticket and replace him with Michelle Obama because Biden did so disastrously badly (in the debate) that Democrats across the country are in utter freefall and complete panic," he said.
Michelle Obama has so far not expressed any interest in joining the race to the White House.
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