Britain’s government has acknowledged that its removal of islanders was wrong, and has granted many citizenship and set aside some funds to improve their lives. But it continues to bar Chagossians from returning and living in their homeland, citing defense and security concerns and “cost to the British taxpayer.”

The governments of Britain and Mauritius have reached a final deal to settle the future of the Chagos Islands but have been barred from signing it by a British judge.

Britain signed an agreement Thursday to hand sovereignty over the contested Chagos Islands to Mauritius, a move the government says ensures the future of a US-UK military base that is vital to British security.