The British government has handed control of the strategically significant Chagos Islands to Mauritius, after the controversial move survived an eleventh-hour legal challenge and months of criticism on both sides of the Atlantic.

Britain signed a multi-billion dollar deal on the future of the Chagos Islands with Mauritius after a last-gasp injunction was overturned, securing itself a lease for the U.S.-UK Diego Garcia air base for the next century.

Mauritius and Russia have agreed to strengthen ties, amid fears that the UK was too hasty in deciding to hand over the Chagos Islands.

The decision to return the islands at a cost to the UK has been made amid welfare cuts and calls to prioritise domestic spending.

Mauritius has fuelled fresh security fears over the Chagos islands deal after announcing it would seek a closer relationship with China. The Chinese ambassador to Mauritius said she supported “deepening full-fledged exchanges and co-operation between China and Mauritius” after a meeting with the country’s prime minister on Thursday.