EU citizens could face problems similar to members of the Windrush generation after Brexit, an expert has warned.
Madeleine Sumption, director of the Migration Observatory at the University of Oxford, said there were parallels between the situations facing the two groups.
She said: "In both cases, we have a group of people who come legally under a liberal immigration regime and – when that regime is tightened up – retain the right to stay.
"In both cases, a key question is whether people can get the right documents showing that they have the right to be here."
The Windrush row has prompted fresh questions over arrangements for processing applications from millions of EU nationals seeking to remain in the UK following Brexit.
Those who have been in the country for five years by the end of 2020 will be able to apply for settled status, meaning they are free to go on living and working in the UK.
People who have arrived by December 31, 2020, but do not have five years residence, will be able to apply to stay until they have reached the threshold, at which point they can seek settled status.
Applicants will have to provide an ID document and a recent photograph, as well as declare any criminal convictions.
The scheme will go live online towards the end of this year and remain open until the end of June 2021.
Sumption emphasised that the process should be a "lot easier" for EU citizens than people affected in the Windrush episode.
She said: "The Government has put a lot of resources into developing a process for giving EU citizens 'settled status' documents that is expected to be much simpler and easier to navigate than other immigration applications.
"That said, however hard the Government works to get 100 per cent of eligible EU citizens through the settled status process, some people won't – for many different reasons, including that some simply won't realise that they need to.
"The more time passes, the harder it becomes to provide evidence about previous periods of residence.
"So a big question for EU citizens is whether significant numbers don't manage to get documentation now.
"If that happens, EU citizens in the future could end up facing similar problems to the Windrush generation today."
The Home Office said it was developing a "streamlined" and "user-friendly" scheme for EU citizens to safeguard their right to stay in the UK.
A spokesman said: "Every EU citizen resident in the UK on the day the transition period ends in December 2020 will be eligible for some form of leave to remain, subject to criminality checks.
"We have committed to ensuring that applications will not be refused on minor technicalities and that caseworkers processing applications will exercise discretion in favour of the applicant where appropriate.
"We will be setting out further details before the summer and EU citizens will have plenty of time to make an application."
The department added it was aware of the challenges of ensuring three million EU citizens and their families understood the need to apply, saying it had launched a national awareness campaign.
Why are you making commenting on The National only available to subscribers?
We know there are thousands of National readers who want to debate, argue and go back and forth in the comments section of our stories. We’ve got the most informed readers in Scotland, asking each other the big questions about the future of our country.
Unfortunately, though, these important debates are being spoiled by a vocal minority of trolls who aren’t really interested in the issues, try to derail the conversations, register under fake names, and post vile abuse.
So that’s why we’ve decided to make the ability to comment only available to our paying subscribers. That way, all the trolls who post abuse on our website will have to pay if they want to join the debate – and risk a permanent ban from the account that they subscribe with.
The conversation will go back to what it should be about – people who care passionately about the issues, but disagree constructively on what we should do about them. Let’s get that debate started!
Callum Baird, Editor of The National
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here