The unnamed prince is believed to have earlier had a row with the 32-year-old aide in a room at the £520-a-night hotel in Marylebone.
Scotland Yard said that a murder inquiry has been launched after post mortem results showed that the victim died as a result of “manual compression of the neck” and a head injury.
The prince is in his 30s and is a distant relative, believed to be a great nephew, of King Abdullah. He was on a sightseeing trip and had been in London for about a month, and was travelling alone apart from the aide.
As a minor royal he does not qualify for diplomatic immunity from any potential charges.