What is the Chagos Islands dispute about?

• Chagos Islands is a disputed territory between Mauritius and the United Kingdom. 
• The Chagos Archipelago was part of the British colony of Mauritius until 1965 when the UK separated the islands to form the British Indian Ocean Territory (BIOT). 
• After Mauritius gained independence from the UK in 1968, the United Kingdom refused to return the Chagos Islands to Mauritius claiming that the island was required to use certain islands in the Indian Ocean for defense purposes. 
• Mauritius claims this separation was illegal and that the Chagos Islands, including Diego Garcia, belong to it.
• The largest island on the Chagos Islands archipelago, Diego Garcia, is where the US and the UK operate a large military base.
• In 2019, the International Court of Justice ruled that Britain should give up control of the islands.
• In the same year, the UN General Assembly adopted a resolution recognising that “the Chagos Archipelago forms an integral part of the territory of Mauritius” and urged UN agencies “to support the   of Mauritius”.

Why in News?

• The United Kingdom and Mauritius have reached a historic agreement to recognize Mauritian sovereignty over the Chagos Archipelago, including Diego Garcia, while ensuring the continued operation of the U.K.-U.S. military base there. 
• The treaty ensures both sovereignty and the long-term security role of the Diego Garcia base in regional and global stability.