Vote on Mauritian request to refer matter of sovereignty to international court of justice seen as test of UK’s standing in Brexit world

The UK is in danger of losing a vote at the UN on the fate of the Chagos Islands, an Indian Ocean archipelago that has been at the centre of a long-running dispute between Britain and Mauritius.

The UN is voting on Thursday on a Mauritian resolution to refer the matter of the islands to the international court of justice (ICJ) in The Hague.

The vote will be seen as a test of the diplomatic influence wielded at the UN by the British foreign secretary, Boris Johnson. If the UK fails to get backing from EU countries and loses the vote it may be portrayed as a blow to the UK’s prestige.

In 1965, three years before Mauritius was granted independence, the UK decided to separate the Chagos Islands from the rest of its then Indian Ocean colony. The Mauritian government claims this was in breach of UN resolution 1514, passed in 1960, which specifically banned the breakup of colonies before independence.

Most of the 1,500 islanders were deported so that the largest island, Diego Garcia, could be leased to the US for a strategic airbase in 1971. Only the US has publicly backed the UK over the islands’ fate. The islanders have never been allowed to return home.

A letter sent on 8 June by Matthew Rycroft, the UK permanent representative at the UN, and circulated around diplomats in New York, warns that a vote to send the matter to the ICJ would “set a dangerous precedent for international justice which would affect us all”.

His letter suggests that the row is over sovereignty and that the dispute should be dealt with as a “bilateral issue” between the UK and Mauritius.



The UK has promised to return the Chagos Islands to Mauritius when they are no longer needed for defence purposes, but has refused to give a date.

Two years ago Mauritius won a ruling at the permanent court of arbitration at The Hague that Britain had acted illegally in the way it has exercised territorial control over the Chagos Islands. The court criticised the UK for failing to consult over establishing a marine protection zone around what is now the British Indian Ocean Territory.

Since then Mauritius has been been more forthright in pursuing its demands on behalf of the native Chagossians who were expelled. It is also pressing for a firm date for an eventual handover of sovereignty.

Mauritius claims it has the support of all the African group of nations at the UN, as well as many states in the non-aligned movement, for its UN motion. Its UN representative also believes that some EU countries, on whom the UK can normally rely, are planning to abstain in the vote.

A document circulated by Mauritius at the UN accuses the UK of adopting a “a regrettably disingenuous position”, blames Britain for “dismembering Mauritius in 1965 contrary to international law” and says that it has refused to discuss “decolonisation”.



If EU countries do not back the UK and Mauritius wins the vote, it may suggest that Brexit has undermined Britain’s international status, moving it towards a position of relative diplomatic isolation.

Spain, which resents the UK’s occupation of Gibraltar, is thought unlikely to vote against the Mauritian motion. Germany, it has been suggested, could also abstain.

Some observers pointed out that the UK often loses votes at the UN general assembly and that defeat would not represent a significant change in Britain’s international standing.



Johnson’s appointment as foreign secretary last year was not welcomed by many countries, suggesting he may have few favours he can call in. His journalism, which has included references to “flag-waving piccaninnies”, has not endeared him towards diplomats around the world.

Diego Garcia was used by the CIA after 9/11 in rendition and interrogation operations, which is expected to further alienate many states from the UK’s cause.



Jagdish Koonjul, the Mauritian representative at the UN, said: “It’s going well … We hope we should be able to carry the vote. For the EU it’s a very difficult choice they have to make … A number of EU countries are torn between supporting issues of principle and their alliance with the UK. I’m expecting there would be abstentions.”

Advisory opinions at the ICJ are normally triggered by a formal request from the UN secretary general. The court can request submissions from member states and those involved in a dispute.

Although its findings are normally non-binding, the ICJ’s advisory opinions carry some legal influence and moral authority.

Prof Philippe Sands QC, who is acting as a legal counsel to Mauritius and will be in New York for the vote, said: “The only international judges who have addressed the matter have concluded – without ambiguity – that Britain’s actions are not consistent with international law, including the obligation to complete the process of decolonisation and Mauritius’ right to self-determination.

“Britain’s continuing occupation of Chagos, and its unwillingness to allow the matter to proceed to the ICJ, are hardly compatible with the country’s avowed commitment to the rule of law.”

A Foreign Office spokeswoman said: “We are disappointed that a resolution challenging the sovereignty of the British Indian Ocean Territory is being put to a vote in the UN general assembly. This is an inappropriate use of the international court of justice mechanism.

“While we do not recognise the Republic of Mauritius’ claim to sovereignty over the islands, we have a longstanding position that we will cede it to Mauritius when no longer required for defence purposes, and we maintain that commitment.”