From Wikipedia:
Since the 1980s the government of Mauritius and the Maldives has sought to regain control over the Chagos Archipelago, which was separated from the British Colony of Mauritius by the UK in 1965 to form the British Indian Ocean Territory. On 23 June 2017, the United Nations General Assembly (UNGA) voted in favour of referring the territorial dispute between Mauritius, the Maldives 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. Judge Abdulqawi Ahmed Yusuf described the UK's administration of the Chagos Islands as "an unlawful act of continuing character". In February 2019, the International Court of Justice in The Hague ruled that Britain should transfer the islands to Mauritius as they were not legally separated from the latter in 1965.
In December 2019 the UK elected a new government under Prime Minister Boris Johnson. How will he react to the UN's ruling? Will the territory continue to be a British possession for very long?