In a video recorded last year, presidential hopeful Mike Bloomberg refers to transgender women as “some guy in a dress.” This is the second time Mr Bloomberg has been recorded making such statements in recent years.

The March 2019 video also has Mr Bloomberg referring to transgender people as “he, she or it” in comments aimed at warning 2020 Democratic candidates against emphasising transgender issues, arguing that they would not play well in parts of America.

Mr Bloomberg joins the other Democrat candidates on stage tonight in his first debate of the primaries — the ninth for the other contenders.

In an interview with Kristen Welker that airs tonight on NBC Nightly News, fellow presidential candidate former Mayor Pete Buttigieg, when asked what Mr Bloomberg has to answer for on the debate stage, said: “I think he has to answer for his treatment of others, for his language and above all for an attitude that seems to have dismissed the humanity of a lot of people.”

Mr Bloomberg’s comments were recorded before he announced his candidacy for the 2020 Democratic nomination at a forum hosted by the Bermuda Development Agency. The clip surfaced shortly after a new campaign ad described the former mayor of New York as being “incredibly sensitive” to LGBT+ issues.

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“If your conversation during a presidential election is about some guy wearing a dress and whether he, she, or it can go to the locker room with their daughter, that’s not a winning formula for most people,” he said.

He made similar remarks at Oxford University in 2016.

Speaking to Buzzfeed, a spokesperson for his campaign defended Mr Bloomberg: “Mike understands that the transgender community has been under attack for decades and the advance of rights has not been equal. In April 2002, during his first year as mayor, Mike signed a sweeping transgender civil rights bill into law.”

They also highlighted that Mr Bloomberg’s company provides comprehensive health care coverage for its transgender employees.