Crown Prince Haakon then revealed that neither he nor Crown Princess Mette-Marit would be present in the courtroom during the trial. Indeed, the couple have scheduled a number of royal engagements during the period. Høiby’s mother – the future queen of Norway, who is facing a lung transplant due to complications from pulmonary fibrosis – will take a ‘private’ trip as the proceedings unfold, and has not yet decided whether it will last for the duration of the trial.

Neither the Crown Prince nor the Crown Princess will make any comments during the trial, though Haakon added that ‘we will follow the case as best we can through the media, and will follow up on Marius during the period.’

Marius Borg Høiby has long been considered the ‘black sheep’ of the Norwegian royal family. Mette-Marit gave birth to her son before meeting Crown Prince Haakon, and Høiby was four-years-old when the pair married in 2001. The union was initially met with widespread scepticism as Mette-Marit was a single mother and a ‘commoner’, one who grew up in difficult family circumstances.

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Crown Princess Mette-Marit, Crown Prince Haakon, and Marius Borg Høiby at the christening of Princess Ingrid Alexandra in 2004

Pascal Le Segretain/Getty Images

Yet Mette-Marit – and her son – won over the public. Although Høiby was never given a royal title or official duties, Crown Prince Haakon raised him as his own, and he joined the royal family at high-profile events. He is said to have a close relationship with his siblings, which has become increasingly difficult to navigate as accusations against him continue to emerge.

It is this complicated relationship that Crown Prince Haakon attempted to explain in Wednesday’s statement. ‘Marius Borg Høiby is not part of the royal family, so in that sense he is free,’ he explained. ‘But we love him, of course, and he is an important part of our family.’

Høiby denies the most serious accusations against him, but plans to plead guilty to some lesser charges when the trial starts, his lawyer Petar Sekulic previously told Reuters news agency.