Prince Harry has arrived at the High Court in London ahead of his showdown against the UK’s Daily Mirror Tuesday.

The Duke of Sussex is set to testify against the British tabloid after accusing its staff of phone hacking and other unlawful reporting.

The exiled royal was seen exiting a black SUV. He arrived sans wife Meghan Markle.

Looking relaxed in a navy suit atop a white shirt, Harry smiled as he entered the building after saying “good morning” to the press waiting outside.

The father-of-two is suing Mirror Group Newspapers (MGN) for damages, claiming its journalists opted for unethical methods to obtain information, as well as using private investigators and phone-hacking tactics.

Harry is set to testify at around 10:30 a.m. local time — which is set to mark the first prince appearance in court in 130 years.

The 38-year-old son of King Charles III will face cross-examination by a lawyer for the Mirror Group Newspapers.

He is expected to spend a full day in the witness box Tuesday, as well as at least half a day Wednesday. 

The prince’s historic appearance comes just a day after he decided to skip out on the first day of the trial Monday.

On Monday, Harry’s lawyer David Sherborne told the court that the duke’s relationship with his brother, Prince William, suffered “mistrust” at the hands of the Mirror publisher.

The case against Mirror Group is the first of Harry’s multiple lawsuits against the media to go to trial — and one of three alleging tabloid publishers unlawfully snooped on him.

Mirror Group has maintained it had used documents, public statements and sources to legally report on the royal.

Despite his client’s absence Monday, Sherborne told Judge Timothy Fancourt that Harry had flown from his Los Angeles home late Sunday after attending his daughter Lilibet’s second birthday, but could not attend court Monday.

“His travel arrangements are such and his security arrangements are such that it is a little bit tricky,” Sherborne told the judge.

“I’m a little surprised,” Fancourt replied, noting he had instructed Harry to be in court for the first day of the highly anticipated case.