“He’s coughing in the middle of my answer, I don’t like that,” he is filmed snapping at his chief of staff Mick Mulvaney after being asked when he will release his financial records. “If you’re going to cough, please leave the room.
“You just can’t, you just can’t cough,” Mr Trump added, shaking his head emphatically.
The episode came during a TV interview broadcast on Sunday, during which ABC’s George Stephanopoulos asked Mr Trump probing questions about his financial history, the Mueller investigation, Barack Obama and decreasing poll numbers. It was not clear whether Mr Mulvaney actually left the room.
During the interview, Mr Trump repeatedly made false claims about special counsel Robert Mueller’s investigation, which found evidence of Russian interference in the 2016 US election and suspicious links between Mr Trump’s campaign and Russian officials.
Right before the coughing episode, the interviewer asked Mr Trump whether he would release his tax returns, something Democratic opponents have been pressing for since before he became president.
Having upbraided his chief of staff for his coughing fit, Mr Trump resumed the interview, saying: "So at some point, I look forward to, frankly, I’d like to have people see my financial statement. Because it’s phenomenal."
Mr Stephanopoulos interrupts to say: "It's up to you."
The president replies: "No, it’s not up to me, it’s up to lawyers, it’s up to everything else. But they’re asking for things that should never be asking for, that they’ve never asked another president for. They wanna go through every deal that I’ve ever done. They’ve, what they’re doing is a disgrace.”
The interviewer says: "But other presidents have turned over their tax returns.”
Ignoring the interruption, Mr Trump says: “They’re trying to do: step, step, step. They wanna keep it going as long as possible to try and demean and hurt as much as possible, so they can possibly win the presidential election.”