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 "some personal problems" and that he may "spend a lot of money" on a campaign, but "he will not do very well."

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.

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

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 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 back in July 2016.

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