President Trump said Wednesday that he would welcome the opportunity to run against Democratic presidential candidate Pete Buttigieg, his first public acknowledgment of the South Bend, Ind., mayor's burgeoning candidacy.

In an interview with David Webb on SiriusXM, Trump speculated that he may end up campaigning for the presidency in 2020 against Sen. Bernie Sanders (I-Vt.), former Vice President Joe Biden or "the mayor from Indiana," referencing Buttigieg without mentioning him by name.

"I think I'd like running against him, too," Trump said of Buttigieg. "But it'll be interesting to see it unfold."

The interview marked Trump's first direct comment on Buttigieg, who formally entered the Democratic field of prospective candidates on Sunday and has surged in recent polling.

The 37-year-old launched an exploratory committee earlier this year as a relative unknown in an increasingly crowded presidential primary field.

Since then, Buttigieg has attracted strong crowds at campaign events and raised an impressive $7 million for his campaign in the first quarter of 2019. That figure put him ahead of prominent candidates such as Sens. Elizabeth Warren (D-Mass.) and Kirsten Gillibrand (D-N.Y.).

Buttigieg has made a number of comments criticizing Trump, saying earlier Wednesday that the president uses "white guy identity politics" to divide working- and middle-class Americans.

In addition to his first jabs at Buttigieg, the president in Wednesday's interview chided Sanders and Biden, two candidates he speculated a day earlier might be the two front-runners for the Democratic nomination.

"I think I put out yesterday, it could be Bernie, and it could be Biden," Trump told Webb, who is a contributor to The Hill. "And I think Sleepy Joe's going to have a hard time. He's, you know, 1 Percent Joe. I don't think he's going to make it, and I don't, I don't know that Bernie - it may be Bernie has the most spirit over there right now."

Biden has yet to formally announce his candidacy, though he is widely expected to do so soon. He and Sanders have been at or near the top of most Democratic primary polls in recent months.

Trump appeared to be irked by Sanders's appearance Monday night on a Fox News town hall event, tweeting several times about the Vermont senator and questioning the network's audience selection.