Mauritius v. United Kingdom was an arbitration case concerning the status of the Chagos Archipelago and the attempts of the United Kingdom government to create a Marine Protected Area in British Indian Ocean Territory. The dispute was arbitrated by a arbitral tribunal constituted under Annex VII of the 1982 United Nations Convention on Law of the Sea. The Permanent Court of Arbitration was asked on the 31st of March 2011 to function as registry in the proceedings.