Crawley Borough Council has called on the government to review its decision to hand sovereignty of the Chagos Islands to Mauritius.
Crawley is home to the largest Chagossian community in the UK, with around 3,500 people having settled in the town.
During a meeting of the full council, Conservative leader Duncan Crow tabled a motion setting out the council’s opposition to the sovereignty decision.
It has been more than 50 years since Chagossians were evicted from their home on Diego Garcia – the largest island in the group – to make way for a US military base.
In October, it was announced that a deal had been reached which would see the UK hand over the islands to Mauritius – though no resettlement of Diego Garcia would be allowed.
Mr Crow said it was a ‘bad deal’ and the UK had been ‘played’ by Mauritius.
He added: “What really rubs salt in the wound is that no representative of the Chagossian community had a seat at the table.
“This is a deal not being done for them, it’s a deal being done in spite of them.”
Mr Crow said the current government had got things wrong in making the deal – and the previous government got it wrong in starting the negotiations in the first place.
Pointing out that Mauritius is 1,300 miles away from the Chagos Islands, he said the only people the UK should be speaking to about sovereignty were the Chagossians themselves.
He added: “The UK government needs to take a step back, stop the deal and start a genuine engagement with the Chagos community.”
The motion received unanimous support from Crawley councillors.
Leader Michael Jones added an amendment which called on the government to look into reparations for the Chagossians for their displacement both in this country and overseas, and to take practical action to help them return to their homeland if they wish.