President Donald Trump on Friday taunted former New York Mayor and multibillionaire Michael Bloomberg amid reports that he is preparing a late entry into the already crowded 2020 Democratic primary race.

"He's not going to do well but I think he's going to hurt [former Vice President Joe] Biden actually," Trump, 73, said of Bloomberg. "There's nobody I'd rather run against than little Michael."

"He doesn't have the magic to do well," Trump added. "Little Michael will fail."

Trump also said that Bloomberg has "got some personal problems" and that he may "spend a lot of money" on a campaign, but "he will not do very well."

It was unclear which problems Trump was referring to. The White House did not immediately provide clarification.

Bloomberg, 77, has not formally announced his presidential campaign yet. A source told CNBC that while Bloomberg is "still not sure" if he will launch a White House bid, he is "troubled" by the current state of the Democratic primary field.

Still, he has already secured a few high-profile endorsements. Judge Judy Sheindlin, longtime star of daytime courtroom reality show "Judge Judy," wrote in an op-ed last month that Bloomberg "is the realist we need" in the White House.

On Friday, billionaire Leon Cooperman — who recently challenged Elizabeth Warren on what he called her "soak-the-rich" rhetoric — said he will support Bloomberg if he enters the 2020 Democratic primary.

"I'm a huge fan of Michael. I know him personally. It's a breath of fresh air. Unless he changes his stripes, he will have my unequivocal support," Cooperman told CNBC in an extensive phone interview.

CNBC previously reported that Bloomberg was prepared to spend at least $100 million if he ran for president.

A spokesman for Bloomberg did not immediately respond to CNBC's request for comment on the president's remarks.

Bloomberg's possible bid garnered mixed reactions among Democrats, some of whom see his more moderate politics as a disruptive force in the top ranks of the primary, where the relative centrist Biden is competing against Warren and self-described democratic socialist Bernie Sanders.

"He really believes he would be a good president," longtime Democratic strategist Joe Trippi told CNBC. "At the same time, I'm sure from his perspective he's very worried about Bernie or Warren taking the nomination [and] losing to Trump."

Trump has long made efforts to brand his political enemies with derisive or demeaning nicknames. He regularly referred to his 2016 Democratic opponent Hillary Clinton as "Crooked Hillary," and has called House Intelligence Committee Chairman Adam Schiff, D-Calif., who is leading the impeachment inquiry into Trump's efforts with Ukraine, as "Shifty Schiff."

Trump, who stands seven inches taller than Bloomberg, has slighted the former mayor with the "little" moniker before.

″'Little' Michael Bloomberg, who never had the guts to run for president, knows nothing about me. His last term as Mayor was a disaster!" Trump tweeted in July 2016.

Trump spoke to reporters outside the White House on Friday morning, en route to Atlanta for fundraising events and to speak at the rollout of the "Black Voices for Trump Coalition."

Bloomberg's moves came amid speculation that Clinton, who won the popular vote in 2016 despite losing the Electoral College to Trump, may also be weighing a presidential run.

At The New York Times DealBook conference in New York City on Wednesday, Clinton avoided an outright "no" when asked about running for president in 2020.

"I have always been a very, very slow runner," she joked, later adding, "I think I would have been a really good president."