The UK has signed a £3.4bn ($4.6bn) deal to hand over sovereignty of the Chagos Islands to Mauritius, while retaining control of a UK-US military base on Diego Garcia - the largest of the islands. Prime Minister Sir Keir Starmer said the 99-year agreement to lease back Diego Garcia will cost the UK £101m a year, and is necessary to protect the base from "malign influence". Mauritian Prime Minister Navin Ramgoolam said the agreement completed "the total process of decolonisation". But UK