Migrants moved from secretive UK military island after three years

In letters sent to the Tamils on Friday from the Home Office, they were told they were being granted temporary entry clearance to the UK “outside of the Immigration Rules” to allow them to consider their “long-term options”.

It stressed that the offer did not “constitute permanent settlement in the UK or recognition of refugee status by the UK government”, and said the group would not be permitted to work.

The government says the Chagos Islands, known as the British Indian Ocean Territory (Biot), are “constitutionally distinct” from the UK, with the unusual status leading to the long legal dispute.

Most of the Tamils have been awaiting final decisions on claims for international protection – which the United Nations says is akin to refugee status – or appealing against rejections.

In total, eight have been granted international protection, meaning they cannot be returned to Sri Lanka, the BBC understands.

Successive governments have previously said that bringing the Tamils to the UK would risk creating a “backdoor migration route”.

But the government said on Monday that arrangements had been made to ensure this did not happen, citing a deal to send future arrivals to St Helena – another UK territory some 5,000 miles away.

“Once a sovereignty agreement with Mauritius is fully in place they would then take responsibility for any future migrants,” the spokesperson said.