The British Indian Ocean Territory is a UK Overseas Territory. It is administered from London and there is no British diplomatic or consular representation there.
The British Indian Ocean Territory (BIOT) is not a tourist destination. Access is restricted and a permit is required in advance of travel. There are no commercial flights and mooring permits are only issued to yachts in exceptional circumstances. Access to Diego Garcia is only allowed for those on pre-authorised official duty. See Entry Requirements.
The following is a hazard warning for vessels lawfully travelling through BIOT waters: there are reports of a large unsecured mooring dolphin (part of a floating dock) fouled on the sea bed close to a reef in the Territory. As at 19 February 2017 the latitude / longitude is 06 08.5 S 071 43.2 E. The object is scheduled to be removed during the course of 2017.
There is a low threat from terrorism. See Terrorism.
Source Article from https://www.gov.uk/foreign-travel-advice/british-indian-ocean-territory