The Chagos Archipelago

Map of Indian Ocean showing location of Chagos Archipelago and Environment (Preservation & Protection) Zone which was proclaimed as a Marine Protected Area on 1 April 2010.

"The Advisory Opinion given by the International Court of Justice on 25 February last has made it clear that the excision of the Chagos Archipelago from Mauritius prior to our accession to independence was unlawful. The Court has also ruled that the United Kingdom must end its unlawful administration of the Chagos Archipelago as rapidly as possible. This is indeed a historic ruling. We will leave no stone unturned in our efforts to complete our decolonisation and to enable the free movement of all Mauritians within our entire territory and in particular the return of those of Chagossian origin to the Chagos Archipelago."

Pravind Kumar Jugnauth Prime Minister of Mauritius 07 March 2019


The Chagos Archipelago, which is claimed by the United Kingdom as the British Indian Ocean Territory (BIOT) lies about 1,770km east of Mahé (the main island of the Seychelles). It consists of about 60 low-lying coral islands, and covers some 640,000 sq km of ocean. The total land area is only about 60 sq km.

Diego Garcia, the largest and most southerly island, is 44 sq km in land area. It houses the US Naval Support Facility, a Naval and Airbase with a small (circa 40) Royal Naval and Royal Marine contingent from the United Kingdom.

Access to BIOT

The United Kingdom controls all access to the Territory, for which a permit is mandatory. There are no commercial flights and permits are only issued to yachts in safe passage. Tourism and visits are not encouraged by the UK or US Governments.

Yachts are permitted to moor at specified locations in Salomon and Peros Banhos atolls for a maximum stay of 28 days at a fee of £50 for each 7 days - FCO BIOT Entry Permits [Visiting Vessels Mooring Fees and Permit Regulations 2006 Amendment Regulations 2010].

Access to Diego Garcia

Access to Diego Garcia is further restricted and is only permitted to those with connections to the military facility. No unauthorised vessels or yachts are permitted to approach within 3 nautical miles (the limit of the Territorial Sea).

The US/UK Exchange of Notes 1976 [see page US/UK Agreements] defines those who may enter the island:

                  • Members of the Forces of the UK and US
                  • The BIOT Commissioner and public officers of the BIOT
                  • Representatives of the UK and US Governments
                  • Contractor Personnel (subject to normal immigration requirements)

In addition, the UK Government is permitted to grant access to "members of scientific parties wishing to carry out research on Diego Garcia and its environs, provided that such research does not unreasonably interfere with the activities of the facility". Prior consultation for this is required with the US.

Aside from these groups, any access requires prior consultation with US authorities.

Page last edited 13 Oct 2018