The fire broke out at 0530 GMT on the 'Hurricane', a boat carrying 12 other tourists and 14 crew members.
The three tourists who died had chosen not to dive that day, while the other 12 were attending a briefing on board when the fire started.
The cause of the fire was an electrical short circuit.
The local authorities and police will conduct a full investigation into the cause of the fire.
Britain's Foreign Office is in contact with local authorities and supporting nationals involved.
Scuba Travel, the British holiday company, expressed condolences to the families and friends of the deceased.
LONDON DAILY ARCHIVE
Tragedy in Egypt's Red Sea: Three British Tourists Die in Boat Fire
Three British tourists died in a boat fire in Egypt's Red Sea on June 11, 2023.
12 June 2023 · 22:49 UTC