Andrew Mountbatten-Windsor has been served with a summons compelling him to give evidence in a fraud trial in the High Court on or around 15 December, the BBC understands.
The witness summons will see him giving evidence and taking questions, in a case in which a wealthy woman alleges she was cheated by her former financial adviser.
Mountbatten-Windsor is not accused of wrongdoing, but he could face difficult questions about his financial arrangements as it is said that he was in receipt of some of the disputed payments, including a transfer to him of £750,000.
His court appearance will be the first public questioning Mountbatten-Windsor has faced since his BBC Newsnight interview in 2019.
It is also believed that Mountbatten-Windsor is the first royal since the 19th Century to be sent such a witness summons.
Such an unusual royal moment is likely to receive widespread media coverage - not least for the opportunity to hear the former Duke of York's first public comments since being stripped of his titles.
Last month, a judge gave permission for Mountbatten-Windsor to be called as a witness.
The summons was issued this week, with the case set to begin from mid-November and with Mountbatten-Windsor to appear as a witness around the 15 December, which is usually in person, but could be on video.
There have been many questions in recent years about Mountbatten-Windsor's personal finances - and challenges about a lack of transparency - and this case promises to give a rare opportunity to hear his own explanations about his financial dealings.
The case will hear allegations made by Nebahat Isbilen, an elderly Turkish woman, who says her former adviser Selman Turk misled her and used her wealth to his own advantage.
Turk has strongly denied dishonesty.
Mountbatten-Windsor will be asked to give evidence related to disputed questions about the handling of Isbilen's money.
According to court documents, Isbilen claimed she was misled by Turk into paying £750,000 to Mountbatten-Windsor, believing it was for help with a passport.
Turk has denied the allegation and says this payment was a gift made on Isbilen's own initiative to create goodwill with the then duke and had nothing to do with a passport.
The case covers payments made at the very end of his time as a working royal.
The transfer of money came the day after Mountbatten-Windsor recorded his BBC Newsnight interview, which was then broadcast the following night, and was soon followed by the then Duke of York stepping down from royal duties.
In 2021, Isbilen's lawyers contacted the then Prince Andrew and the money had been paid back, but the forthcoming court case will consider claims about Turk's behaviour, with Mountbatten-Windsor set to be a significant witness.
Court documents show there will be questions about another significant sum of money paid from Isbilen's account - around £768,000 in January 2020.
Turk has claimed it was a loan to Mountbatten-Windsor for the purchase of a chalet in Switzerland - a suggestion which is contested by Isbilen and had been challenged in previous court hearings.
Turk had met Mountbatten-Windsor in autumn 2019 through the Pitch@Palace project, a Dragon's Den-style pitching event run by the former duke.
That had led to social gatherings, bringing together Turk and his family, Isbilen and the then Duke and Duchess of York.
Justice Adam Johnson has said that, given the seriousness of the allegations, Turk should have access to "the evidence he considers relevant and material".
That meant that Turk wanted to use Mountbatten-Windsor's evidence and has been successful in summonsing him for that purpose.
Turk's representatives, Janes Solicitors, said he denies the claims of dishonesty and looks forward to being vindicated in court.
Mountbatten-Windsor has been approached for a response.
The trial at the High Court is expected to begin later this month.
