Marius Borg Høiby, son of Norwegian crown princess, enters rehabilitation months before abuse and rape trial begins

The stepson of Norway's Crown Prince is being treated for substance abuse just months before he prepares to stand trial.

Marius Borg Høiby, 28, is accused of 32 crimes including domestic abuse and rape, most of which he denies, and faces 10 years in prison if convicted.

The case has shaken Norway's royal family, which has faced numerous battles over the past year.

In August, Norwegian prosecutors indicted Høiby after a lengthy investigation.

The trial will begin on February 3 next year and run until March 13, in Oslo's District Court.

Høiby's two defence lawyers, Ellen Holager Andenæs and Petar Sekulic, have confirmed to news outlet TV 2 Norway that their client was being treated for his drug abuse.

"We can confirm that he is receiving treatment," Sekulic said.

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Weeks after his arrest in August last year, Høiby issued an apology to Norway's royal family.

"I know that my actions have greatly affected you", he said in a statement, adding he took "full responsibility" for what had happened.

Høiby said he was under the influence of "alcohol and cocaine" at the time of the alleged incident, adding he "struggled with substance abuse" and would seek professional help.

Following his release from custody in November, Høiby went straight into rehabilitation. There were some reports that initial stint took place in London.

His legal team has also expressed concern for Høiby ahead of the trial.

"It would be strange if we weren't concerned about the media pressure that we are now seeing develop," Andenæs said.

"And it probably won't get much better as the case gets closer to going to court.

"It will be very tough for him. It's not an easy situation to be in."

Høiby is the son of Crown Princess Mette-Marit from a previous relationship before she married the heir to the throne, Crown Prince Haakon.

Høiby has no royal title or official duties. He was officially recognised as a member of the royal family by King Harald before the wedding in 2001, but never received a royal title.

He was first arrested on August 4 and charged with causing bodily harm and damaging property during an first arrested on August 4 inside her Oslo apartment.

Princess Märtha Louise and Shaman Durek to appear on TV

Meanwhile, two of the royal family's other divisive figures are set to appear in a joint television interview later this week.

Princess Märtha Louise and husband Shaman Durek have spoken to Swedish journalist Carina Bergfeldt for her self-titled talk show.

On Instagram Bergfeldt confirmed the couple had filmed an episode of her show, due to air on Friday, where they spoke about "about love, racism, sickness and the massive criticism at home in Norway".

But the interview nearly didn't happen.

Shaman Durek, who is currently having dialysis and needs a kidney transplant, had to undergo four hours of treatment before taping and the couple's plane was nearly an hour late.

The studio audience was also prohibited from having their mobile phones, which had to be handed over to security.

Princess Märtha Louise and Shaman Durek have found themselves in hot water with the palace again after appearing in the documentary Rebel Royals: An Unlikely Love Story on Netflix last month.

Recently, there was a renewed push to remove Princess Märtha Louise's royal title with anger growing over her involvement in the documentary. The poll found that seven out of 10 people want her to be stripped of her royal title.

Hours after the documentary's release the palace issued a statement which said the film was "a breach of the agreement" made in the wake of Princess Märtha Louise's royal exit three years ago.

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