Donald Trump gave evidence for just three minutes on Thursday in a defamation trial to determine how much he may owe a writer for calling her a liar after she accused him in 2019 of rape.
E Jean Carroll, 80, is seeking more than $10m (£7.87m) in damages over his denials when he was US president that he attacked her in a Manhattan shop in the mid-1990s.
The limits on Trump's testimony in the civil case were placed on him by US District Judge Lewis Kaplan.
The judge told jurors they must accept the findings of another New York jury that awarded Ms Carroll $5m (£3.93m) after concluding he sexually abused her at the store and defamed her in a similar denial in October 2022.
The current trial at Manhattan federal court focuses only on statements Trump made in June 2019 while he was US leader. Those claims had been delayed for four years by appeals.
During his brief stint testifying, Trump answered questions from his lawyer Alina Habba.
The former president said that Ms Carroll "said something I considered a false accusation".
A lawyer for Ms Carroll objected and Judge Kaplan told the jury to disregard the remark.
Trump later said: "I just wanted to defend myself, my family and frankly, the presidency."
That also drew an objection and another instruction from the judge for the jury to disregard it.
As Trump left the New York courtroom, he shook his head and repeatedly said: "This is not America. This is not America. This is not America."
Trump, 77, has denied the accusations for the last five years and continues to attack the former Elle columnist on the presidential election campaign trail.
Ms Carroll was present as Trump was sworn in as a witness in court.
The former president, who had big victories in the New Hampshire primary on Tuesday and the Iowa caucuses last week, appeared relatively subdued in court before his testimony compared to previous appearances.
Trump is also facing four criminal cases as the presidential primary season heats up.
He has been juggling court and campaign appearances, using both to argue that he is being persecuted by Democrats.