James Eadie, the government's lawyer, said they needed a decision by 12pm GMT in order for the deal to be agreed on Thursday and "everyone is standing by".
He said the delay was damaging to British interests and "there is jeopardy to our international relations … [including with] our most important security and intelligence partner, the US."
The earlier injunction had been granted following action by Bertrice Pompe, a British national who was born in Diego Garcia and has criticised the deal for excluding Chagossians.
It was the latest legal action in the last two decades brought by members of the wider Chagossian diaspora, many of whom ended up in Britain after being forcibly removed from the Indian Ocean archipelago more than 50 years ago.
They have said they cannot endorse an agreement they were not consulted on, while critics have also said the deal plays into the hands of China, which has close trade ties with Mauritius.
In 1965 Britain detached the Chagos Islands from Mauritius — a former colony that became independent three years later — to create the British Indian Ocean Territory.
Reuters
Court lifts injunction allowing Chagos Islands handover to Mauritius to proceed
Injunction had blocked deal at last minute
Image: Leon Neal/Getty Images
Britain can conclude a deal with Mauritius on the future of the Chagos Islands on Thursday after a judge at London's high court overturned an 11th-hour injunction which had blocked the agreement being signed earlier.
Lawyers representing a British national born in the Chagos Islands were granted an interim injunction in the early hours of Thursday morning, postponing the formal signing of the treaty which aims to secure the future of the strategically important US-UK Diego Garcia air base.
But judge Martin Chamberlain lifted the injunction following a hearing later on Thursday, clearing the way for Britain to sign the multibillion-dollar deal to cede sovereignty of the Chagos Islands to Mauritius.
The deal, the details of which were first announced in October, would allow Britain to retain control of the strategically important base on Diego Garcia, the largest island of the archipelago in the Indian Ocean, under a 99-year lease.
Following the court's decision to overturn the injunction, the agreement is due to be signed off later.
UK agrees to Chagos Islands sovereignty deal with Mauritius
James Eadie, the government's lawyer, said they needed a decision by 12pm GMT in order for the deal to be agreed on Thursday and "everyone is standing by".
He said the delay was damaging to British interests and "there is jeopardy to our international relations … [including with] our most important security and intelligence partner, the US."
The earlier injunction had been granted following action by Bertrice Pompe, a British national who was born in Diego Garcia and has criticised the deal for excluding Chagossians.
It was the latest legal action in the last two decades brought by members of the wider Chagossian diaspora, many of whom ended up in Britain after being forcibly removed from the Indian Ocean archipelago more than 50 years ago.
They have said they cannot endorse an agreement they were not consulted on, while critics have also said the deal plays into the hands of China, which has close trade ties with Mauritius.
In 1965 Britain detached the Chagos Islands from Mauritius — a former colony that became independent three years later — to create the British Indian Ocean Territory.
Reuters
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