Government ministers have revealed the reason scores of EU nationals were wrongly sent letters threatening them with deportation.
The Home Office apologised after an “administrative error” led to more than 100 people being told they had a month to leave the country or face being booted out - amid uncertainty over their status in the UK post-Brexit.
The gaff came to light after a Finnish academic who has lived in the UK with her British husband for most of the last ten years posted about it on Facebook.
Green Party co-leader Caroline Lucas submitted a Parliamentary question asking ministers to spell out exactly what led to the mistake being made.
Immigration minister Brandon Lewis revealed those who had been sent the letters had made unsuccessful applications for a registration certificate - a document required by extended family members of EU citizens and EU citizens who want to apply for British citizenship or sponsor a partner’s visa application.
“The error made was an incorrect interpretation of the consequences of an EEA national’s unsuccessful application for a Registration Certificate,” he said.
“We have agreed to meet any reasonable associated costs incurred as a result of this error. We should be able to quantify the total cost in due course.”
Lewis added a total of 106 letters were sent in error between 11 and 16 August 2017 and said he had written personally to all those affected to apologise.
Lucas, who has lobbied for the government to give cast-iron assurances to EU citizens that they will be able to remain living in the UK after Brexit, said: “Mistakes like this are simply not acceptable - and add further worry to the lives of EU nationals already anxious about their status here in the UK.
“These are people who are our neighbours and friends and family, yet the government is treating them with contempt as second class citizens.
“The government is turning lives upside down by callously playing hardball over Brexit and creating a ‘hostile environment’ for migrants. Ministers need to get a grip, and make sure that an error like this never happens again.”
Theresa May has vowed to protect the right of 3.2 million EU nationals to stay in the UK after March 2019, even though freedom of movement will be abolished.