Mauritius formally challenges Britain’s ownership of Chagos Islands

Britain’s ownership of the Chagos archipelago has been formally challenged after the Mauritian ambassador to the UN, Jagdish Koonjul, raised his country’s flag above the atoll of Peros Banhos.

In a ceremony on Monday at 10.30am local time, Mauritian officials sang their country’s national anthem and the red, blue, yellow and green standard was raised up the flagpole.

Koonjul said: “We are performing the symbolic act of raising the flag as the British have done so many times to establish colonies. We, however, are reclaiming what has always been our own.”

A pre-recorded message by the Mauritian prime minister, Pravind Jugnauth, was broadcast on a speaker to the Chagossians, Mauritian officials and media assembled on the beach.

“This is the first time Mauritius has led an expedition to this part of its territory,” he said. “I feel sad that I have not been able to be part of this historic visit.

“I’m delighted that our Chagossian brothers and sisters are able to travel to their birthplace without any foreign [ie British] escort.

“The message I wish to give out to the world, as the state with sovereignty over the Chagos archipelago, is that we will ensure a wise stewardship of its territory – over its maritime security, conservation of the marine environment and human rights, notably the return of those of Chagossian origin.”

A metal plaque secured beneath the flagpole said: “Visit of the Mauritius delegation to Peros Banhos archipelago, Republic of Mauritius, in the context of the scientific survey of Blenheim Reef.”

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In a phone call to the Guardian shortly after the flag was raised, the Mauritian prime minister said: “This is a very emotional moment for me and a very historic time for us because we are able to raise our flag on our own territory.

“The international community and international institutions have already decided that this is our territory. What we are doing is legitimate.”

Asked what would happen if UK officials later removed the Mauritian flag, Jugnauth said: “I don’t know what they are going to do. If they remove the flag, this will amount to a provocation on their part. The UK is not abiding by international law judgments.”

After the ceremony, the crew of the cruise ship Bleu de Nîmes, chartered by Mauritius, arranged a barbecue on the beach.

Wifi communications from the ship have been disrupted for the past 24 hours. Another vessel was seen nearby. It was not clear whether this was a UK-owned fisheries protection ship.

The Mauritian government is making clear that the time has come for its legal victories in international courts and the UN to be translated into facts on the ground.

A number of British Indian Ocean Territory signs were removed from the island in the process of the landing and the flag-raising. Most had warned – ineffectively, given the rubbish strewn around – that litter should not be left by visiting yacht crews.

The debris that has accumulated on Peros Banhos, and the Salomon islands, where there are buoys for anchoring, suggests that the UK government’s authority in the archipelago is already being flouted and its professed environmental concerns for the islands have not been rigorously adopted.

A Mauritian flag was also raised by three Mauritian officials on Salomon atoll during the landing on Sunday afternoon.

On Monday morning, shortly after dawn, one of the only permanent residents of Peros Banhos was sighted: a donkey trotting along the sand. A small herd has survived on the island since the British deported its entire human population in 1972.