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

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, according to BBC.