David Snoxell is Co-ordinator of the Chagos Islands (BIOT) All-Party Parliamentary Group.

The Chagos Archipelago was excised in 1965 from Mauritius before independence, and its 1,500 inhabitants deported between 1968-73.

For the last five decades the FCO (Foreign & Commonwealth Office) has prevented the Chagossians from returning to their islands in the Indian Ocean, and has denied them the right of abode. It has resisted both political and legal attempts at promoting a resolution of the issues.

The Queen’s Speech announced an integrated security, defence and foreign policy review focussing on the UK’s international role, post Brexit. Will this review include policy towards the Chagos Islands and the exiled Chagossians following the ICJ (International Court of Justice) Advisory Opinion last February? It found the UK in unlawful occupation of the Islands, demanded the UK return them as rapidly as possible to Mauritius and also that it cooperate in facilitating the resettlement of Chagossians.

In May, the UN General Assembly (UNGA) endorsed the Opinion, and set a deadline for implementation of 22 November 2019. It was ignored by Her Majesty’s Government. In 20 years of national and international litigation these are the latest challenges to UK sovereignty and Chagossian resettlement.

The UK is isolated in the UN on this issue. Now that it is on the UN General Assembly agenda it will continue to dog British diplomacy. Litigation, which began in 1999, continues in the Court of Appeal. The case could again reach the European Court of Human Rights and the International Criminal Court (ICC) given that expulsion of a people is akin to a crime against humanity.

On 27 December, the BBC quoted the Mauritian PM as saying that he was exploring the possibility of bringing charges of crimes against humanity against individual officials at the ICC. This is not an idle threat. FCO needs to be conscious of the risk it runs by continuing to ignore the will of the ICJ and the international community.

Support for Mauritius and the Chagossians was in the Labour Party and Scottish National Party manifestos. During the debate on the Queen’s Speech on 19 December, Patrick Grady, the SNP Chief Whip, and a Vice Chairman of the Chagos Islands All-Party Parliamentary Group, referred to the Government “ignoring rulings of the UN General Assembly and the International Court of Justice on the Chagos Islands”.

I expect the APPG to be re-established later in January, and to take up where it left off at its last meeting on 17 July 2019. At that meeting the Group issued a statement urging the next government “to respect the will of the United Nations, the ICJ Advisory Opinion and the requirements of international law, which from the signature of the UN Charter in 1945 remains the keystone of the UK’s foreign policy and commitment to international order based on the rule of law”.

The UN Secretary General is expected to report early next year to the UNGA on the implementation of its resolution. The Mauritian Prime Minister will be in the UK for the UK/African Investment Summit on 20 January, which will be hosted by the British Prime Minister. This would provide an opportunity for the two leaders to discuss Chagos and set the ball rolling for more detailed talks.

Mr Johnson has some experience of Chagos. As Foreign Secretary he had a meeting with the previous Mauritian PM at the UN in September 2016 at which he is reported to have said that he would “fix it” if Mauritius held off tabling the proposed UNGA resolution. It therefore seems likely that he will want to settle the issues.

In the UNGA debate, the UK suggested that Mauritius cannot be relied upon when it comes to the security and operations of the US base, without providing any evidence to support this claim.

For several years the Mauritian Government has confirmed, as Prime Minister Jugnauth did on 21 November in a statement to the National Assembly, that “it fully recognises the importance of the military base in Diego Garcia and will take no action that will impede its continuing operation”.

Moreover, Mauritius has made clear to the United States that it stands ready to enter into a long-term arrangement in respect of Diego Garcia.” Under the 1966 UK/US agreement BIOT (British Indian Ocean Territory) was made available for the defence purposes of both nations and extended for 20 years in 2016. It comes to an end in 2036, but there is nothing to stop both parties amending that agreement and entering into new arrangements with Mauritius well before then.

The Indian Ocean could become an area of competing political and security influence. India and China have an increasing interest, as does Australia. The US and the UK maintain that the defence role of Diego Garcia remains crucial. However, there is to be a scrutiny of the Ministry of Defence and its expenditure. If the UK were to divest itself of Chagos it could reduce in excess of £10m off its annual defence and FCO budgets, and free up for other duties the 40-50 service personnel stationed on Diego.

It would be rash to predict what might happen in 2020. What can safely be said is that the current alignment of events makes 2020 a propitious year to bring about an overall settlement of the issues. It would be irrational for any government that believes in the peaceful settlement of disputes, the rule of law, and human rights to find any further excuses not to negotiate a settlement. It must be in the UK national interest to do so, especially now the UK is in search of a new role in the world, following withdrawal from the EU and the uncertainty of our special relationship with the US.

To continue to ignore Chagos will have implications for the UK’s role and permanent seat on the Security Council, as happened in November 2017 when for the first time the UK judge on the ICJ failed to be re-elected. For a founding member of the UN and ICJ it would be humiliating to lose our seat on the Security Council and relegate the UK to a minor part on the international stage.

The government must bring an end to this humanitarian tragedy, which continues to undermine our reputation for upholding the rule of law and human rights. We cannot preach to other governments what we are unwilling to do ourselves. And we cannot afford further litigation and international isolation.