The government has considered building an asylum processing centre on a remote UK territory in the Atlantic Ocean.
The idea of “offshoring” people is being looked at but finding a suitable location would be key, a source said.
Home Secretary Priti Patel asked officials to look at asylum policies which had been successful in other countries, the BBC has been told.
The Financial Times says Ascension Island, more than 4,000 miles (6,000km) from the UK, was a suggested location.
The Foreign Office is understood to have carried out an assessment for Ascension – which included the practicalities of transferring migrants thousands of miles to the island – and decided not to proceed.
However, a Home Office source said ministers were looking at “every option that can stop small boat crossings and fix the asylum system”.
“The UK has a long and proud history of offering refuge to those who need protection. Tens of thousands of people have rebuilt their lives in the UK and we will continue to provide safe and legal routes in the future.
“As ministers have said we are developing plans to reform policies and laws around illegal migration and asylum to ensure we are able to provide protection to those who need it, while preventing abuse of the system and the criminality associated with it.”
No final decisions have been made.
Labour’s shadow home secretary Nick Thomas-Symonds said: “This ludicrous idea is inhumane, completely impractical and wildly expensive – so it seems entirely plausible this Tory government came up with it.”
Alan Nicholls, a member of the Ascension Island council, said moving asylum seekers more than 4,000 miles to the British overseas territory would be a “logistical nightmare” and not well received by the islanders.
He also told BBC Radio 4’s Today programme that the presence of military bases on the island could make the concept “prohibitive” due to security concerns.
Ascension Island key facts
- The volcanic island has no indigenous population. The inhabitants – fewer than 1,000 – comprise the employees of the organisations operating on the island and their families
- The British territory has a military airbase – jointly operated by the RAF and the US – and has been used as a staging post to supply and defend the Falkland Islands
- Its first human inhabitants came in 1815, when the Royal Navy set up camp to keep watch on Napoleon, who was imprisoned on the island of St Helena
- It is home to a BBC transmitter – the BBC Atlantic Relay station – which sends shortwave radio to Africa
In order to be eligible for asylum in the UK, applicants must prove they cannot return to their home country because they fear persecution due to their race, religion, nationality, political opinion, gender identity or sexual orientation.
Asylum seekers cannot work while their claims are being processed, so the government offers them a daily allowance of just over £5 and accommodation, often in hostels or shared flats.
Delays in processing UK asylum applications increased significantly last year with four out of five applicants in the last three months of 2019 waiting six months or more for their cases to be processed.
That compared with three in four during the same period in 2018.
In Australia, asylum seekers can be sent to an offshore processing centre while their claims are processed.
Australia has centres on the Pacific island nation of Nauru and another on Manus Island in Papua New Guinea.