The eldest son of Norway's crown princess has been charged with 32 offences, including four counts of rape, a prosecutor says.

The charges against Marius Borg Høiby, 28, include the abuse of a former partner and violations of restraining orders against another former partner.

He was born from a relationship before Crown Princess Mette-Marit married Crown Prince Haakon, who is the future king of Norway.

Mr 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 told Reuters news agency.

He could face up to 10 years in prison if found guilty of the most serious charges.

He has also been charged with filming the genitals of a number of women without their knowledge or consent, prosecutor Sturla Henriksbø told reporters.

"He does not agree with the claims regarding rape and domestic violence," Mr Sekulic said of his client, according to Reuters.

Speaking about the charges against his stepson, Norwegian Crown Prince Haakon on Tuesday said it was up to the courts what would happen, adding that everyone involved in the case "probably finds it challenging and difficult", Norwegian public broadcaster NRK reported.

The four alleged rapes are said to have occurred between 2018 and 2024, with one of them allegedly taking place after his arrest, according to NRK.

Mr Høiby, who does not have a royal title or official duties, was arrested three separate times last year, in August, September and November. He had been under investigation since his August arrest on suspicion of assault. In June, police said he was suspected of three rapes and 23 other offences.

The prosecutor said the trial could take place in January and last some six weeks.