Defence Minister John Healey says about 4,500 people are in Britain or in transit under the secret programme.
The United Kingdom set up a secret plan to resettle thousands of Afghan people in Britain after an official accidentally disclosed the personal details of more than 33,000 people, putting them at risk of reprisals from the Taliban, court documents showed.
A judge at London’s High Court said in a May 2024 judgement made public on Tuesday that about 20,000 people may have to be offered relocation to Britain, a move that would likely cost “several billion pounds”.
Britain’s current Defence Minister John Healey told Parliament that around 4,500 affected people “are in Britain or in transit … at a cost of around 400 million pounds [$540m]” under the programme known as the Afghan Response Route.
The government is also facing lawsuits from those affected by the data breach.
A Ministry of Defence-commissioned review of the data breach, a summary of which was also published on Tuesday, said more than 16,000 people affected by it had been relocated to the UK as of May this year.
The breach revealed the names of Afghans who had helped British forces in Afghanistan before they withdrew from the country in chaotic circumstances in 2021.
The details emerged after a legal ruling known as a superinjunction was lifted. The injunction had been granted in 2023 after the Ministry of Defence argued that a public disclosure of the breach could put people at risk of extra-judicial killing or serious violence by the Taliban.
The data set contained personal information of nearly 19,000 Afghans who had applied to be relocated to Britain and their families.
It was released in error in early 2022, before the Defence Ministry spotted the breach in August 2023, when part of the data set was published on Facebook.
The former Conservative government obtained the injunction the following month.
Prime Minister Keir Starmer’s centre-left government, which was elected last July, launched a review into the injunction, the breach and the relocation scheme, which found that although Afghanistan remains dangerous, there was little evidence of intent by the Taliban to conduct a campaign of retribution.
Healey said the Afghan Response Route has now been closed and apologised for the data breach, which “should never have happened”.
About 36,000 more Afghans have been relocated to the UK under other resettlement routes.
British troops were sent to Afghanistan as part of a deployment of the United States-led so-called “War on Terror” against al-Qaeda and Taliban forces in the wake of the September 11, 2001, attacks on the US.
At the peak of the operation, there were almost 10,000 British troops in the country.
