A Saudi prince beat and strangled his male servant to death in a frenzied sexual assault at their luxury London hotel suite, a British court has heard.

Saud Bin Abdulaziz Bin Nasir al Saud, 34, who is a grandson of Saudi Arabia's King Abdullah, killed Bandar Abdullah Abdulaziz on February 15 after abusing him for weeks, the court heard.

The 32-year-old victim was found with severe injuries including bite marks on his cheeks in a bed in the suite at the Landmark Hotel, which he was sharing with the prince, prosecutors said.

Prosecutor Jonathan Laidlaw told the jury at the Old Bailey in London, England's Central Criminal Court, that Saud had admitted the lesser charge of manslaughter but denied murder and a separate count of grievous bodily harm.

Mr Laidlaw said the two men had been staying together at the hotel for nearly a month as part of an "extended holiday" that had also taken them to Italy, Hungary, the Czech Republic and Morocco.

Saud had claimed the pair were friends and that he was heterosexual, but the court heard the prince had ordered gay escorts in London and had frequently looked at websites for gay massage parlours and escort agencies.

"The defendant's concealing of the sexual aspect to his abuse of the victim was for altogether more sinister reasons and it tends to suggest that there was a sexual element to the circumstances of the killing," Mr Laidlaw said.

Bloodstains found on the pillow and the room were "consistent with the victim having been the subject of a series of separate assaults before he was killed", he added.

Saud told police they drank at the hotel bar until the early hours of the morning on February 15 before returning to the room and that when he woke in the afternoon he could not rouse the victim, the court heard.

The prince was "shocked and upset" and had tried to clean up some of the blood and wash some of Mr Abdulaziz's bloodstained clothing when hotel staff and a Saudi embassy staffer came to the room, Mr Laidlaw said.

A post-mortem found that Abdulaziz had suffered heavy blows to the head, injuries to the brain and ears and severe neck injuries which were "consistent with an episode of manual compression".

The prince appeared in the dock with a shaven head and listening through an interpreter. His father is a nephew of King Abdullah and his mother is one of the king's daughters.

- AFP