On 23 June 2017, the United Nations General Assembly (UNGA) voted in favour of referring the territorial dispute between Mauritius and the UK to the International Court of Justice (ICJ) in order to clarify the legal status of the Chagos Islands archipelago in the Indian Ocean. The motion was approved by a majority vote with 94 voting for and 15 against.[37][38]
In February 2019, the ICJ in The Hague ruled that the United Kingdom must transfer the islands to Mauritius as they were not legally separated from the latter in 1965. The UK Foreign Office said the ruling is not legally binding.[39] In May 2019, the United Nations General Assembly affirmed the decision of the International Court of Justice and demanded that the United Kingdom withdraw its colonial administration from the Islands and cooperate with Mauritius to facilitate the resettlement of Mauritian nationals in the archipelago.[40][41] In a written statement, the U.S. government said that neither the Americans nor the British have any plans to discontinue use of the military base on Diego Garcia. The statement said in a footnote: "In 2016, there were discussions between the United Kingdom and the United States concerning the continuing importance of the joint base. Neither party gave notice to terminate and the agreement remains in force until 2036".[42][7]
In June 2020, a Mauritian official offered to allow the United States to retain its military base on the island if Mauritius succeeded in regaining sovereignty over the Chagos archipelago.[43]
Chagos Marine Protected Area
On 1 April 2010, the Chagos Marine Protected Area (MPA) was declared to cover the waters around the Chagos Archipelago. However, Mauritius objected, stating this was contrary to its legal rights, and on 18 March 2015, in light of the Mauritius v. United Kingdom case, the Permanent Court of Arbitration ruled that the Chagos Marine Protected Area was illegal under the United Nations Convention on the Law of the Sea as Mauritius had legally binding rights to fish in the waters surrounding the Chagos Archipelago, to an eventual return of the Chagos Archipelago, and to the preservation of any minerals or oil discovered in or near the Chagos Archipelago prior to its return.[44][45]
Hand over of the island to Mauritius
On 3 October 2024, the UK prime minister Keir Starmer announced in a statement with the Mauritian prime minister Pravind Jugnauth that the UK will hand over the Chagos islands to Mauritius. The joint base on the island will stay, with the UK initially taking a 99 year lease of the base from Mauritius. Mauritius will be allowed to begin resettlement on the Chagos Archipelago, but not on Diego Garcia due to the sensitive nature of the base. US president Joe Biden welcomed the agreement, saying that it was a "clear demonstration that through diplomacy and partnership, countries can overcome long-standing historical challenges to reach peaceful and mutually beneficial outcomes".[3]