Northern Ireland's First Minister has slammed a mooted UK digital ID card scheme aimed at tackling illegal migration as "ludicrous" and "ill-thought out".
The so-called 'Brit-Card' would allow the verification of a citizen's right to live and work in the UK.
The Sinn Féin vice president said that the proposal was an attack on the Good Friday Agreement.
"The British Prime Minister's proposal for a mandatory digital ID card is ludicrous and ill-thought out.
"This proposal is an attack on the Good Friday Agreement and on the rights of Irish citizens in the North of Ireland."
The proposal, as first reported by The i Paper, is to be subject to consultation and thought to require legislation.
The announcement will be made by British Prime Minister Keir Starmer during a speech on Friday.
Under the plans, anyone starting a new job or looking to rent a home in the UK would be required to show the card on a smartphone app.
It would then be checked against a central database of people entitled to live and work in the UK.
It is hoped this would reduce the attraction of working in the UK illegally, including for delivery companies.
This comes amid calls from French President Emmanuel Macron for the UK to reduce "pull factors" for migrants to cross to come to the UK.
A total of 1,157 people have arrived on small boats in the last week, according to Home Office statistics.
Prime Minister Starmer is due to speak at the Global Progress Action Summit in London alongside Australian prime minister Anthony Albanese and Canadian prime minister Mark Carney.
Earlier this month, Mr Starmer said an ID card system could play an "important part" in stopping illegal migration.
He said things had "moved on" since the debate over ID cards during the last Labour government in the 2000s.
He had told the BBC: "We all carry a lot more digital ID now than we did 20 years ago, and I think that, psychologically, it plays a different part."
Home Secretary Shabana Mahmood has also previously been positive about the policy.
The UK has only previously had mandatory ID cards during wartime. The last ID scheme was scrapped in 1952.
John Major's government ran a consultation on reintroducing an ID card scheme in the 1995, but they were never brought in.
His successor, Tony Blair, then considered a voluntary ID card, but it was not fully rolled out amid objections from the Liberal Democrats and Conservatives.
Mr Blair has since called for their introduction.
His calls were backed up by Labour campaign group Labour Together earlier this year which has been closely linked to Mr Starmer and the Government.
The thinktank published a 30-page document in June in favour of the 'Brit Card'.
In the report, it said: "The Labour government has the opportunity to build a new piece of civic infrastructure, something that would become a familiar feature of daily life for everyone in the country.
"It would support better enforcement of migration rules, and protect vulnerable British citizens from being wrongly denied their rights."
The civil liberty group Big Brother Watch has again warned against their introduction.
A petition started by the group has reached more than 101,000 signatures.
In a letter to Mr Starmer on Wednesday, the group said: "Mandatory digital ID is highly unlikely to achieve the government's objective of tackling unauthorised immigration.
"The proposed schemes fundamentally misunderstand the 'pull factors' that drive migration to the UK and would do very little to tackle criminal people-smuggling gangs or employers and landlords who operate 'off the books'.
"Instead, it would push unauthorised migrants further into the shadows, into more precarious work and unsafe housing."
Ed Davey told the Liberal Democrat conference this week that his party would need to properly "scrutinise" any details, but said it was not necessarily against the policy.
Responding to the ad-hoc poll during an event in Bournemouth, Mr Davey replied: "Times have changed, and that is why I am saying 'let's look at it'."
He added: "There are models that may answer our objections as liberals."
